i have the 2.5x ncstar on my 22/45 ruger 5 1/2" bull barrel auto. after several hundred rounds it is still doing great! they are well worth testing. just be sure ya know it's a gamble when ya buy it. maybe you'll get by, and maybe you won't.
i am well pleased with the 2.5x model. couldn't be happier with it's performance on the 22 auto, so far.
i had the 2.5x7 model, but only for a very short period. it looked fine, and is longer in length than the 2.5x model(not sure by how much). i upgraded that gun to a 2x7 burris, so i can't say how it would have held out for the long haul.
well worth a try on light kickers, if you go into it with the right mindset(possible...win,loose, or draw).