Late to the party...
If you like money, buy a Contax. You will have more money.
I went to see Eikoh Hosoe the other night (blog) and the people on either side of me were shooting Leicas while I hammered away KETHUNK KETHUNK with my SLR. They are quieter than the Contax, even (in one guy's case) with the spring motor. The shutter in the G2 is metal, similar (identical?) to that in the Konica Hexar RF. Still, I could hear them. And I know when they shot, and I'm happpy to say that I'm convinced my pix were better "it's not the camera..." etc.
As for people shooting with Contax G2's, Robert Frank and William Eggleston have them (Egg uses it in the recent documentary movie), as does Luc Delahaye (who shot Winterreisse with his). I occasionally see people carrying them on the news in Iraq, at the White House, and so forth. My buddies Eddie and yoshi shoot documentary with G2 in harsh conditions and it just keeps coming back for more.
Still, if you are having equipment anxiety then always buy the most-expensive, so that you can sleep at night (that's only half-joking! it's a common, common issue -- look at Diane Arbus's fretting over the Pentax 6x7)