Bought 3 once, lured in by the low price and "Lifetime Warrenty". The first one fell apart after firing one 30rd mag in a 10/22, the second came apart after one shot on the M305, adjustment turret fell right off. The dealer just gave me a total refund since on the 30 or so he had sold, 29 had already come back. The third is still plugging along on my CZ .17HMR. Although the focus seems less sharp after every use.
All in all, save your money and purchase quality once, instead of junk every year. Like I tell my wife, "I'm not rich enough to buy cheap junk over and over again."