Have had the JP49 Speed board for about two months and finally had the chance to test it out. Please note that I have never sailed a speed board before, so my comments will be more from a recreational point of view.

The board is well finished and very very light, comes with a 26cm fin, and I set the foot straps from holes 2-3 (front and back) as the normal setting is too small.
I'm 92KG and currently use Isonic94 and RSS Mark3's (7.0/6.2).
Our runs at Golden beach in a Northerly are about 900m long with room for a 200m broad reach through 10-40cm chop as the speed run. This makes it difficult to get a good 10 second time as you are having to slow down to turn back upwind at the end.
At first I went out on I94/7.0/35cm SL9, wind was 16-22knots at a guess, which is very consistant for Golden Beach. There are usually always a few dead spots on the run, caused from the northern buildings, so stop/start is quite normal, sorry I mean sink/start.
The I94/7.0 was runnig at consistant 33.4 10 second times on the GPS. So thought it was a good opportunity to try the JP. I wasn't sure if the JP49 would take a 7m ( website says it can) so decided to rig the 6.2 instead for the 1st try.
1st run was on JP49/6.2 RSSM3 and Caspar 29.
I'm sure I starred at it for 5 minutes wondering wether or not to purchase a snorkel!
Anyway thought what the hell and jumped on. Unbelievably it jumped straight onto the plane, didn't round up in the process and off I went. The foot strap placements are the same as the Isonics basically so getting in the straps was easy for me. The 1st thing i noticed was the boom felt oddly high, so dropped it 1cm after the 1st run.
The ride was super smooth and I could sail around at angles not to dissimilar to the isonic. On the run back I went for a broad reach and hit 34.4 for 10 seconds. Although I felt under powered it seemed to keep planing extremely well, must be the slightly different rocker compared to a slalom board.
The JP's speed on a reach was superior to the slalom board, and it felt just too easy. The nose sits low, and doesn't move around when going through chop.
Not sure what else I can say about it, will try to gybe it next time. The 7.0m should work fine also, but will have to let you know later. I'm very pleased with it and for such a small board, if the winds consistant, it can be sailed in moderate winds quite easily!