I want to fit a lower geared triple to my Vaya rather than the 52-39-30 Ultegra I currently have. Only on the longest steepest downhills and with a hurricane force tailwind do I ever use the 52. I can get up most everything with the 30 but on my last trip to the Cascades with some really long (50 mile) climbs I felt I would have been happier spinning a smaller gear. As I can fit wider tyres I may use it on some trails too.
Merlin currently have an SLX triple with 48-36-26 rings for £75 and an XT M771 with the same ring combo for £109. Both are 170mm. Is the XT worth the extra £30? It's been ages since I rode with a 170mm crank, would I notice any difference? I'm a serial spinner.
Is there owt else I should consider?