I bought a Smith and Wesson 617, 4 inch,10 shot and haven't looked back! With the speed loaders and loading block I can run through 200 rounds before I enen think about it! My regular CCW is a 4 inch GP100 so the 617 isn't bulky at all, matter of fact I just change speed loader pouches and drop it rite in the same holster! I can say that it does help my DA shooting skills for much less $$! Only draw back is the lingth of pull takes a few mins to adjust when switching from one to the other. My favorite woods walking gun has to be my old Ruger Bisley 22lr. It just seems so petite and well balanced, but still shoots like a lazer!
The 617 is a fantastic gun, runs like a Swiss watch, accurate and looks great! I will admit to not having shot the SP101, although I have handled one in the shop and it feels very good in my hand. Most reviews I read are that the 617 will out shoot the SP101, but every gun is different. I find myself jonesing for a S&W 63 real bad, but try not to look at them when in the gun shop!