Not everyone likes the BB30 standard. But they want to buy a frame that has a BB30 bottom bracket shell. No need to despair, get the frame and then purchase SRAM's BB30 to BSA Bottom Bracket Adaptor Kit. Once it is pressed into the BB30 shell, your bottom bracket will function like any other English-threaded bottom bracket. Install your favorite external bottom bracket, your favorite internal bottom bracket,
This isn't an easy home install, so you might want to take it to a shop. Claimed weight of the SRAM BB30 To BSA Bottom Bracket Adaptor Kit is 60g.