I used a Tasco World Class Plus on my .270 for about 6 years with no problems. But.....the seventh year it went south and went big time. A gun that had been shooting 1/2" to 3/4" groups went to not even hitting the paper half the time. I put a Leupold on it and it has been fine since. I got my son a .22 last year for Christmas and put a 3X9X40 Vari-XII on it. This year he's getting a .308 and you'd better believe it will have a Leupold on it too. No more Tasco for me.