Originally Posted by
Barrettscv
Will the XT Shadow RD shift as well as the Ultegra?
Barrett, the only way to know for sure with your setup is to buy one and run it yourself. Nab a used RD-M771 on ebay. If you can't get it to work then re-sell it.
Originally Posted by
Wordbiker
According to Shimano the Shadow is compatible with 11-32 or 11-34 only.
With a fixed upper knuckle the angle is set for a specific derailleur path and will give less than optimal performance with anything other ratios. The only Shadow derailleur that is adjustable from road to mountain cassettes is the Saint, but it won't handle a triple. I'd go for the Ultegra, or if you can find one, a pre-Shadow XT.
I've been running crisp and clean with RD-M971 XTR Shadow and 9spd 11-23 DA the last two seasons on 3 separate bikes. YMMV and I can't say about 10spd as it is not in my experience.