I am assuming a Shimano 9 spd cassette can be substituted for a 9 spd SRAM cassette, true? Currently, I have a SRAM cassette on a Bontrager hub, but want to switch over to Shimano (probably XT level).

The original SRAM cassette seemed to wear unacceptably, even though I measure the chain (with a Park chain checker) and replace the chain when it's between 0.75 to 1.0% stretch points.

Anybody find SRAM to wear quickly, compared to Shimano?

In my (humble) opinion, I think quality level for quality level, SRAM is just as good, perhaps a little better, or a little worse. As far as interchangability, no problems. Many manufacturers, including TREK and Cannondale mix and match Shimano chains, shifters, and DRs with SRAM cassettes on their new bikes. It's a good thing SRAM is around to keep Shimano in line. Your experience is different than mine, but it's kinda like the old Chevy/Ford debates, and I won't get into that, but I'll bet others will...OHB

Fair enough, I'm hoping to avoid a debate. I'll try a Shimano XT level cassette and see what happens. The SRAM is the original, so I'm not sure which model (I could look in build spec, but I'm too lazy). BTW - I much prefer SRAM chains over Shimano. I concur that competition is a good thing.

The two manufacturers cassettes should be interchangable even if all of the shifters and rear derailleurs aren't.

BTW, by the time a chain has "stretched" 0.75 to 1.0%, most of the cogs on the cassette will be hosed no matter who made it. If you want to keep a cassette for a long time, change the chain before 0.5% stretch (1/16" in 12") has occured.

Yeah you shouldn't have any problems. I swapped my SRAM PG-970 cassette with a Shimano XT M-760 and it works fine. In terms of quality, I found the SRAM quite good, but haven't used the Shimano long enough to comment on it. I changed to Shimano because I found the SRAM cassettes much heavier.

I see a politician in the making

Don't go for XTR then! Those things wear like they're made from butter.

I use XT - very happy with it too. Pretty hard wearing stuff and pretty light too. I can't fault it.

Done - I just installed the Shimano XT 760 cassette with new SRAM PC991 chain. Thanks for all your input and comments.