I've had an SR22 now for a couple years and have have fired nearly 1000 rounds through it of a great variety of LR ammo. Two years ago I tested 32 different rounds from sub-sonic to hyper velocities of the various brands one would typically find at sporting goods stores and gun stores. I chronoed this gun along with 5 other guns of various barrel lengths to see the differences and how the ammo performed. All but one gun were Rugers. The SR22 fired everything really well, but the ammo that did the worst was all of the various Remington LR rounds (e.g. Goldern Bullet) that not only had problems with FTE but also FTF and plenty of ST . . . not to mention really poor consistency with high SD's. I fired Yellow Jackets, Stinger's, Velociters, Interceptors and Winchester's Hyper Speed's. The SR22 did well with all of these and had no malfunctions of any kind with these high velocity rounds. Other than those, I found the CCI Mini-Mags HP performed very well and is what I typically like to fire is this gun and there's good velocity and I find great consistency with it out of my SR22.
BTW, I actually bought this gun for my wife as I've tend to like shooting my MKIII Target since the grip on the SR22 is a little small for my hands. But my SR22 is fun to shoot, it's reliable and a breeze to clean (especially compared to a Mark III ;-) ).