Riley, thanks for looking and here are your answers below, all board info, specs etc are on this page: http://www.islesurfboards.com/inflatable-stand-up-paddle-boards.aspx
*Max weight is around 200lbs for 10ft and 245 for 12'6
*When pumped to capacity they are rock hard and have very little flex, they of course do not have the rigidity of a solid epoxy hard board but come very close and the portability and durability is amazing!
*All boards come with a pump with PSI gauge for air pressure. Max is 15 PSI and will be shown on gauge. They are impossible to over inflate unless you use an air compressor and this is not recommended.
*Both are great but pure flat water 12'6 for sure and if you wanna mess around in small surf and have a smaller board and lower price the 10 is a great option.
Hope this helps and happy paddling!