I have a Ruby with a compact double. I found that it did not have enough low gears to get me up the hills. (Nothing is flat in the Santa Cruz mountains.) I now have a mountain bike cassette and derailleur and I love it!

The problem with Shimano is that they make an 11-34 or 11-36 10 speed derailleur for mountain bikes and pair it with a Shadow derailleur. Apparently this derailleur is not compatible with road bike shifters. After much searching on the Internet, I found that some people had bought the new cassette and paired it with an older Shimano Deore rear derailleur. I bought the pieces and had them installed, even though it is not to spec and bike stores don't seem to want to do this. It works fine, as long as I don't cross chain.

Even though I now have my bike working as I want, it was a struggle. If I was to buy a new bike, I would probably get a triple - or I'd have the bike shop where I bought it install the larger cassette and derailleur before I took it home.