Bream it would be good to know what you're going to do with the tallboy, having had mine for 3 or 4 months now, and having raced it a bit I'd say it definitely goes better on the long events. In which case you'll be looking for reliability and comfort over light weight.
Also are you going to ride it at trail centres or down rocky stuff, I took mine on the Afan Monster and it was just great on the technical rocky descents, but if money was no object then I'd have a Rockshox Reverb on my Christmas list.
I'd agree with Algore go 3x10, I'd struggle to see the benefits of the 2x10 as it really isn't a stand up and slog machine (imho).