I would find someone who bought a bunch of Rem Golden Bullet .22LR and found that it was horrible in their semi-auto, and try and get it cheap for practice. I shoot mostly Win followed by Fed.

As far as carry load, I would probably go with a 40 gr Target load or similar. The most important quality is not penetration, but reliable ignition with the rimfire. I would find the most reliable .22 LR and then see which of those hits to POA. With bulk .22LR, the duds seem to be of a higher ratio.