Be careful when you say the DeltaZ autos are "even legal in CA", which might be taken to imply that if they're legal there, they're legal anywhere. That would be patently untrue.
CA has a wierd law which specifically allows autos with blades under 2". In a lot of other jurisdictions (the state of NJ, for example) ALL autos are illegal, no matter the size, with the standard Military & LE exceptions.
A popular mail-order self-defense company was advertising a CA-auto in this manner, and I sent them an e-mail correcting them. They politely thanked me, but I don't know if they've changed their ad copy.