I have a NAA Pug with Big Dot Xs front sight that I sent back to NAA to have the .22LR cylinder fitted. All data I have seen suggests that a 40gr projectile, whether LR or Mag, from such a short barrel has a speed variance that is negligible and the increased blow by from the cylinder while shooting .22mag is an annoyance on the support hand. I have been able to maintain decent accuracy (8" plate/head) at 5-7yds with both calibers of ammo, emptying the cylinder in under 3 seconds. As with anything, practice helps. The only cons I have found is the capacity, anemic calibers, and having to remove the cylinder to reload.