I had a Millett 4-16x50 Tactical and it was ok, optics weren't bad, tracked ok, held zero for the most part, but in the end I just wasn't happy with it sold it on ebay and got almost what I paid for it I just didn't feel it was worth the $300.00+ I paid for it.
FYI: Nikon makes a new scope specifically made for the .22lr. Heard its pretty good for the money.