I like the ruggedness of the Ruger's. The 6" is a GP-100, the 4" is one of my "carry" guns, and is a Security-six. Both are .357's, both were new condition, but bought used for $350 and $300 respectively. The "little one" is a 2" Taurus ultra-lite titanium in .38spl/+p, and was bought since it was used, and "cheap". It is my alternate carry gun. I am pleased with that Taurus, but have held a Taurus .22 that was not carefully assembled. I aslo own a S&W 36 snubbie (out on loan to someone who needed something better than a .22), and oddly enough, my Taurus has a better DA trigger! THAT was a surprise, and is not representative of all S&W or Taurus DA triggers. FWIW, the snubbie has had over 1500 rounds sent out of it in the past 5 months with no issues.
The GP and the S-six are very similar, but the GP is actually a bit beefier, as the top strap is visibly thicker, among other details. I personally recommend the security six, if you like a 4" .357, as they are often found in great shape for $300 or less. I have a really old "service-six" (fixed sight version) that I personally put over 8,000 rounds thru, and it still locks up tight. I got it for $75 nearly 15 years ago. These old "six-series" Rugers will eat a steady diet of hot magnum ammunition for a looong time, and still be handed down to someone. Good luck in the search!
Fabricator