Ok, I have to vent. I decided to put a new chain on my MTB, in the interest of preserving the rest of my drivetrain. The chain I took off measures less than 12-1/16" for 12 links, so I figued the cassette would be fine. Both the cassette and chain had maybe 2 months of riding on them. I throw on a new chain, and it skips in every gear. Useless. I used to get 2 seasons out of a 7 speed cassette, and 1 season out of a chain, no problem. This 9 speed crap is way too fragile for mountain bike use. To add insult to injury, it costs 2x as much. Don't even get me started on the excessive wheel dish....that's another rant.
I went back to 7 speed at the back, and it works great. Same gear range, just not as closely spaced. Much more sensible for off road, IMO.