Being in the industry this long you'd think I would know but board bags never really been something I use unless traveling. Last week I got my new Kalama Performance LB style performance SUPs. Both 28 wide and 9/ 10ft each. Now I'm chasing a decent cover that's not flopping around like a moo moo. Cheers
Don't know about the fit of the Sup bags but I recently bought a Curve Surf bag for my 4'9 foil board and it's such an incredible bag! Super padded and well detailed for very low price.
I'd also second a vote for Surfaids but I actually find them quite expensive, guess you pay for custom. No problem with quality and service, excellent.
I have custom Surfaids bags, which are excellent for fit and I think fairly reasonably priced. Fabric, colour and features are a little basic but they work very well.
I have a 4'9" Curve wing foil bag for my 5' Gofoil board. It fits like a glove lengthwise and the the 20mm foam around the tips is bomb proof. The bag is way too wide but that's less of an issue on a short board that doesn't live on roof racks.