BDC for a rimfire is more of a marketing gimmick. There's too many loads to make a BDC turret or reticle accurate. Also, I chronographed a few .22lr rounds out of my 10/22 last fall and was surprised how far off muzzle velocities were. Stingers were barely 1500 fps, Blazer was just over 1100. Mini mags were very close. This was with an 18.5" carbine barrel, sporter chamber. Now as for red dots vs. scope, it all depends on what kind of accuracy you are expecting. For plinking I don't like scopes on my .22s. They just annoy me. I prefer a red dot for the kind of shooting I like. What you prefer is up to you. Try both, switch them around and see what your eyes prefer.