When I was geeking out on cranksets and comparing price vs weight, I found that I could get a carbon SRAM crankset for the same price as a RF Turbine but the weight was 100g lighter. The RF Next is another 100g lighter than the SRAM but also $200+ more. Now I have too many bikes with GXP cranksets to change now.
I have done the air shaft swap a couple of times on some Pikes, and yes it's relatively straightforward. My local bike shop has given me some amazing prices lately so this time I just let them do it.