So I'm home now and checked --

The front derailleur is Shimano XT (rear is SRAM X-0; that's what had me confused). The chain rings are the ones that came with XT Hollowtech II cranks.

Earlier today, I called the shop and spoke to a mechanic there. He said that while of course I should bring it in and they would look at it, rubbing issues are common for extreme sizing (XS, XL, etc) on full suspension bikes -- the frames can't be sized that way and meet spec perfectly. He also said that rubbing the chain against the bottom of the derailleur cage, while annoying, is not damaging to the components, just noisy.

All of which would be fine and dandy *if* it had been disclosed to me prior to buying the bike, not left for me to discover. Prior to this I was riding a medium frame Sugar. It was way too big for me, yes, but it's not like I had experience with XS frames. At the time I did express that having a quiet bike was important to me (the Sugar was so noisy I felt like it would come apart at any moment), and I did express concern about getting something as small as the XS, but was assured it would be the best fit. And specs indicated that the standover height on the S would be an issue. Unfortunately, this was a case where they only had the M frame at the shop, and I had to choose sight unseen. So I really don't know if the S would have been better for this issue or not ... and it is true that I have had some gnarly wrist issues, so my biggest concern was getting a bike that would not be too big and put pressure on my wrists from being stretched out. Argh. I just wish I could remember exactly how all those conversations half a year ago played out.

DH postulates that, buying that high-end of a bike, the shop guys assumed I would know this. I don't know that that's a good enough excuse. If I already knew everything, I wouldn't need the shop and would have saved money buying the frame myself and having a friend build it up for me.

My discontent is compounded by the fact that the new bike feels so darn short. I am fairly sure that is just because my old bike had such a ridiculously long wheel base for me. I was able to get away with really not having to move my body much at all. But I'm having to learn how to descend all over again, and feel like I'm way extended over the handlebars all the time. Intellectually I know that this just means I need to learn to get further back behind the seat while descending, but there is still this niggling "what if this bike is wroooong for me?" feeling. And the shifting issue isn't helping, even though, yes, I can always use the middle ring to accomplish the same gear ratios.

Sorry for venting. *Deep breath* Just gotta get out tomorrow and ride the darn bike and remind myself, it's fun, it's fun! I just need to ride it more.