STORY #1:
Yup, about 2 years is what we got out of our Monroe QuickStruts & OE Spec Shocks in our '06 Mazda3. They're a terrible product today in terms of longevity and the lifetime warranty means less to me than ever before. Especially since, after having to replace them AGAIN(even as a DIYer), you still need an expensive alignment. Monroe is not the product they used to be. Read on!
STORY #2:
I put 4 Monroe Struts & Shocks in a 1988 Accord in ~ 1997 and they lasted til I got rid of the Accord in 2006 and were still good at that time. The only reason that I replaced the Struts & Shocks was due to broken front springs on this Accord. So I replaced all 4 shocks/struts & springs.
STORY #3:
I installed Monroe GAS Shocks(Blue) in the Firebird in my signature in 1988 just due to the fact that I never liked the OE shocks.
And I still have them in this car as I write this and they're still fine. The GAS Shock has helped the suspension ride more consistent compared to the OE in terms of(with the OE)...
a) On cold days the car rode hard
b) On HOT day the car rode soft
c) Since installing them in '88(YES 1988), the car rides more consistent all the time between April & October. And it's a ride that I like, somewhere in the middle. Tight around corners and absorbent over bumps/ruts but not supple.