Have you had a 2x10 before? I'd be interested to hear what you think. I hired a Commencal with a 2x10 setup, which is the first I've ridden, so not really enough time to judge but I found the top chainring a tadge high compared to my normal middle when going downhill and with the increased spread at the back I was tempted to stay in it a bit longer on a climb, meaning a double shift when it got steeper. I need to sit down and work out the ratios, as I'm not convinced they work as well as a conventional 3x8/7 but like I say, that's on fairly limited experience so far and familiarity with the ratios may well eliminate those problems.
I've been running with 2 x 9 for over a year now on my Orange Five, just a 22, 32 up front and 11 to 32 cassette, obviously I've kept the same low gears I had with the triple, but lost the higher gears, however, I never used them, and the big ring had just become a bash ring, which is what it has now been replaced with.
When I wear out the current bits I will replace the drivetrain with a 1 x 10 system, get rid of the front mech, and fit a chain guide. I am sure the ratios will be fine as long as I'm not riding on the road very much, on road the gears would be too low.