I am actually a big U2 nut but the 90's stuff is completely forgettable for me.
The first of their stuff was all awesome:
Boy (1980)
October (1981)
War (1983)
The Unforgettable Fire (1984)
The Joshua Tree (1987)
Rattle and Hum (1988)
the signs started with
Achtung Baby (1991) a bunch of just forgettable releases for me....
Zooropa (1993), Pop (1997), All That You Can't Leave Behind (2000)
On the Zooropa Album the last track "The Wanderer" with Johnny Cash is an awesome track. "Beautiful Day" is a good track for the 2000 release. Other than that it was Poop
It seemed like they were trying to experiment musically or something and keep it largely commercially viable and it was just forgettable.
Then you have these:
How to Dismantle an Atomic Bomb (2004)
This is an awesome piece of work that took me back to their originals as far I am concerned. Simply a good album, commercial yeah maybe but it was great stuff.
No Line on the Horizon (2009). It totally got a bad wrap, but is actually a great piece of work IMO. And I think I am in the minority on this one
I highly suggest giving it a chance. The second I bought this one I put it in the Car stereo, thought it was crap was completely disappointed threw it aside after the first listen. I just didn't get it. I let it go for a few days.. took a deep breath and played it again, I ended up playing the living hell out it, once I got it. If you give it a chance listen to it more than once and see if grabs ahold.
But it is all subjective.