The class is at least 2 levels long, sometimes 3, depending on what build you're going for. Seriously, +4 unnamed bonus to STR & CON pretty much all day long? No way should that be given at level 1. Then the class really would be only 1 level long.
Immunity to stunning and criticals is handy, but certainly isn't the reason I've ever taken the class.
Level 4 is only useful if you're going to have no access to healing whatsoever, and I've never found a use for the Flashmorph/Multimorph ability from level 5.