I'm not sure about Ceasar's current status, but there are a number of guys who race Ceasar built thundercats on this forum;
http://www.thundercatinflatable.com.au/forum/
The specs and maintenance requirements of the thundercats should be pretty similar as for the larger thunderbolts. I'm not sure what pressure they typically pump the tubes to, but, being PVC I know that it is fairly high (much higher than what a hypalon boat would be inflated to). Keep in mind that the pressures these guys pump them up to is for racing rather than longevity, and some of them get new hulls every year or two.