I don't know much about Sig's but there isn't anything wrong with the 40 cal round.
I had a Beretta 9000s in 40 and traded it for a Kimber ultra CDP.
A couple of months later I got to missing the 40cal and bought a Glock 23.
A snappy round for sure.
Bought a 229 when they first came out. Your going to love it. I do. Heck bought a 228 and a 226 when they first came out also. Can you tell I like sigs.