I had the same problem about a year ago. I went to the big gun show thinking I was going to walk out with a six-shot, six-inch stainless .357. It would be either a GP-100 or a 686. I still wasn't sure when I walked in.
After examining both, I just like the way the Smith felt in my hand. It just seemed more "refined," somehow. It was about $80 more than the Ruger, which means, for me, that price wasn't an issue. Plus two of my friends who were at the show ran across me, and urged me to go Smith.
So I walked out with the 686, and don't regret it. Not that there's anything wrong with a GP-100.
Same thing happened just a few months ago. I decided I wanted a .44 Mag as a reloading platform. I walked into that show thinking strongly in favor of a Redhawk. Much stronger gun than a 629, heavier. But then I played with a 6.5 inch 629. Again, it just seemed more "refined," somehow, and felt better.
Since I had no intention of loading mega-bomber loads, I chose the 629. Now, if I was going to push loading to the redline, I'd have gone ahead with the Redhawk; no question it's a stronger platform than the 29 series.
So I ended up with two Smiths.