I personally prefer the 4" S&W M617. It just seems to have better balance than the 6". You need to handle one and see what you personally think. But the S&W M617 is probably the best US-made DA 22 revolver out there these days.
You can find as-new or nearly so, S&W M17's and I generally like them better if you don't mind 6-round cylinders.
The Colts are very good too. But they often cost more I vey much like the Colt Trooper Mark III and Officers Model Match as range guns. For the field, I find that I prefer a 4" revolver.