Which way to go

[Tennessee Jed]

You'll do well with that GP100. I've got one that's had many thousand rounds of very warm handloads through it, and it's as tight as it was when I first got it, used, 10 years ago. I had the chance to fire a friend's brand new GP100 recently, and the trigger was noticeably better than mine. I think Ruger's getting better at it.

 

[NIGHTLORD40K]

Dont rule out a clean used Security 6 if you stumble on to one. Yes, they have been out of production for many years, but they really never break or wear out either-

 

[Vlad3572]

I own and shoot Taurus, Colt, Ruger and S&W revolvers. I may have been lucky but I've never had any problems except with a used American Western Arms Peace Keeper.

That said I'm very happy with my Taurus 66 6 inch in .357 Mag. I've put almost 5000 rounds thru it. I've also got 2 more in other calibers. Fit and finish is good. If you can find one at a good price get it.

 

[JTHunter]

sfl_gunner - the Ruger is likely to be your best bet for both quality and price. With all the hoopla of gun buying of late, you may have trouble finding anything in most stores. One source that might not have occurred to you is the local pawn shops. I got my GP-100 4" .357 from a pawn shop about 8 years ago.
You might want to take a set of "feeler gauges" with you so you can check the distance between the front of the cylinder and the "throat" of the barrel (aka the forcing cone).