I am really happy with my Surfaids custom bag.
surfaids.com.au/I suspect the custom bag would be cheaper than some of the name brand off the shelf products. Surfaids definitely use better quality zips than some of the name brands.
I looked at all the various bags and I could not be sure that the bags would fit the board properly. I hate sloppy bags that bang on the roof of the car. They were all around $250+ and had to be ordered in so there was no way to try before buying.
FWIW I recently bought a new foil board. Rather than get a new bag I simply cut down my 8'11" bag to 7'8" and reshaped the nose and tail. It was easy to do with a domestic sewing machine. It's so nice having a board that fits neatly inside the car with a decent bag to protect the car and the board.