When I was 21 I bought a P95dc and my friend bought a sigma. Both good guns. The sigma's trigger can be improved but the user very easily at no cost in about 10 minuets but I'm not sure that it doesn't negatively affect the safety of the gun.
Short answer: Ruger P95. It's tough and can hold it's own against anything on the market. Get some Mec-gar 17 round mags for it and you're GTG.
Might also consider keeping an eye out for a used glock (19 preferably) or Smith M&P
I don't collect guns, I accumulate them.