Can you use a HT2 BB with SRAM GXP cranks?
Theoretically, no, as IIRC GXP spindles are stepped down to 22mm. However, Hope (among others) make a GXP adapter sleeve for the NDS bearing – would have thought this would also work with Shimano BBs but don’t know.
Also do you have to use SRAM chain rings or can you go for middleburn/Shimano etc?
Depends on the crank. Triples have a standard BCD so you can use Middleburn/FSA/Raceface/TA/etc chainrings, Shimano rings have a different offset so may not fit. Don’t know about the 2×10 cranks – anyone know if Middleburn etc. are doing aftermarket rings yet?
Andy