Would a 4/3 oneill mutant be colder than a 4/3 oneill physco 2?

actually, yes it is. my friend and i recently bought those wetsuits (he bought the mutant, i bought the psycho 2) and although they are the same thickness, we later noticed that mine has that zip zen thing (which is like an extra layer for your back on the inside the wetsuit) so its a little bit better than the mutant but they are both great wetsuits. BUT, after watching my friend trying to get out of his suit the other day, the mutant seems like a pain to get in and out of, and it definitely made me happy that i payed a little bit more for mine haha! i love it.