Buy the 11'6 BIC, it's bulletproof and cheaper than anything else. You won't be disappointed. The big dagger board is essential for light wind use. The dagger board can be removed and a plug inserted on the top to give a clear deck for SUP too. If you're in Brissy you're welcome to try mine.

I recently faced the same problem but I haven't tried any of the boards on your shortlist so can't offer an opinion on them.

Another option is to get a centreboard from an old longboard (or a new Algiers rotating CB) and fit it to a good second hand SUP.
The choice of board will always be a compromise between surfing and sailing performance mainly due to rocker and volume.

I have an old Mistral Pacifico that was great to take on the yacht, lake, rivers, etc, or take the dog for a sup or sail (eva deck provided good grip for the pooch) but it lacked a centreboard so had poor upwind ability which limited it's suitability for learners, and general cruising range.

Since I got back into course racing last year I have rediscovered the versatility of raceboards like the F2 Lightning and Mistral Equipe, for cruising as they perform very well in both light and strong winds, and can go anywhere, but while I sometimes use my raceboard as a flatwater SUP, it is unsuitable for the surf.

I had an old Windsurfer centreboard and case from a dearly departed Wally lying in the shed, so a couple of weeks ago I put it into the Mistral Pacifico. Some people have just added another a finbox in the bottom towards the middle of their SUP board, but I wanted a larger foil that could be rotated while sailing.

On both days I tried testing it with the new CB the winds never go over 3kns so am still waiting for the right test conditions.

In theory it should be better than my old Wally for my needs as it is 25% lighter (15kg), has a power box to carry a better fin, is wider so provides more stability for SUPing, and learners, and has full EVA deck for the dog to grip claws into, and now has a decent CB to help it go upwind.

I have used the Pacifico in the surf at a number of places, but it is only good for small waves due to flat rocker, and large volume.

Back in the early '80s my windsurf quiver was a Wally for lightwind and racing and a Malibu surfboard converted with a mast base and footstraps for wavesailing (my avatar pic - this was before the first boom in custom waveboards) and the rigs were very primitive dacron windsurfer full/threeQtr/half sizes.

A modern equivalent all round quiver would be a decent windSUP (with a CB), a good all-round short board for waves/freeride (plenty to choose from), and good all round set of sails (again, plenty to choose from).

If you're in the market for a family windSUP like Eric is, then the weight of a centre board surely is at the bottom of the list of considerations. Up the very top of the list for family toys is durability. The last thing you need when on holidays is the kids dragging your windSUP down to the water and you stressing the whole time that they're going to whack it into a post or a rock. That's where the plastic BIC kills the competitors.

Contrary to what you may believe Al, I find the centreboard is good when the wind is really light, say 5-10 and it allows me to sail upwind easier. When you've got power and a bit of speed the rear fins work ok, but still not as good as a larger slalom type fin would work. I also don't use big sails and find a 6.5m sail more than enough for ease of use for cruising around. I don't use mine in big waves though , only smallish 1 foot bay mush.

Paddles B'mere said..
If you're in the market for a family windSUP like Eric is, then the weight of a centre board surely is at the bottom of the list of considerations. Up the very top of the list for family toys is durability. The last thing you need when on holidays is the kids dragging your windSUP down to the water and you stressing the whole time that they're going to whack it into a post or a rock. That's where the plastic BIC kills the competitors.

Contrary to what you may believe Al, I find the centreboard is good when the wind is really light, say 5-10 and it allows me to sail upwind easier. When you've got power and a bit of speed the rear fins work ok, but still not as good as a larger slalom type fin would work. I also don't use big sails and find a 6.5m sail more than enough for ease of use for cruising around. I don't use mine in big waves though , only smallish 1 foot bay mush.

The plastic Bic is tough but even it wont tolerate being dragged over rocks. An inflatable is the toughest and easiest for kids to carry (its very light) but not that great for surfing! Its always hard to have one board that does everything.

The Naish inflatable at Low Head.

Thanks, all, for the insights. I'm still on the fence about daggerboard vs. removable center fin. Both have their merits for getting upwind. The daggerboard is preferable for deploying at the right time on the fly. The center fin works fine for sailing upwind, but it's big advantage is the ability to remove it completely when paddle surfing is the order of the day. Beyond that, the weight seems to be the big differentiator. The Blend comes in at 26.45 lbs., the Bic at 33 lbs. That's not an insignificant difference in paddle mode. The Bic is a few inches longer and carries 30 addition liters of volume, but neither measurement is a selling point for me in paddle surf mode. It might be as simple as saying the Bic is a windsurfer that SUPs and the Blend is a SUP that windsurfs. Which sadly still doesn't help me decide.

I actually live in the United States. I turned to you all on this forum because I've found your discussions on other forum topics to be always helpful. Thanks for the offers to test a board. I appreciate it. And your thoughtful replies.

I've decided to take a windsurfing lesson next week and see what new info I can glean.

A fixed center fin is a bad idea, it will hit bottom at some point and has tremendous leverage to tear out the fin box or at the least destroy the fin. Also makes the board difficult to carry around, put on the car etc.. A daggerboard can be removed which is what you will do with it most of the time.

I have a Fanatic Fly SUP with an mast base insert and also an inflatable Starboard Astro. The Fly has no centre fin and the Astro has a fixed fin option.
I only ever use the stubby fins supplied with the Astro on it, as the boxes are the stuck on type, not integrated.

My observations of the two is that the Fly is better to paddle, in the flat and in the small surf I take it in. However, it is difficult to make any ground up wind on it sailing it in the surf or flat water, due to the no centre fin and also rounded rails. I have tried teaching some friends and family on it, but it is not ideal due to this and also due to it being quite fragile.

Since I bought the inflatable, I have had quite a few fun light wind sessions sailing it. It performs really well in these conditions and goes to windward well considering the size of the fins. I have no issues with leaving the centre fin in most of the time as is short and wide and the same length as the rear fin.

I have never really pushed it hard, but the friend I bought it off had it planning with a larger pointer type fin.

Great for learners, as it there is not as issue to them or the board will falling onto the board. I also find myself mucking around trying things on it I might not on my Fly in light wind conditions for the same reason.

I have paddled it many times with the centre fin in and if anything it provides a bit more directional stability with no loss in performance. Obviously you would want to remove it for added maneuverability in the surf. But it is noticeably slower to paddle than the fly.

I think inflatables are a great option, made easier if you spend a bit more and buy a suitable 12v pump to inflate them.