I like all things Sig, but I'm not crazy about the DAO trigger.
As for barrel swaps, easy enough, but how much is a Sig factory barrel running if you wanted to bump up from 9mm Luger to .357 Sig ??? What about mags if your changing to .357 Sig ? 9mm Luger and .40 S&W basically fit each other in the mag department so you could possibly use the same mags but after a barrel purchase to another caliber, how much would you have in the gun ???? $850 ? $1,000 ?
I like it, just gonna have to let it digest a bit.