It looks a bit like that BXT hardtail frame that came out a while back due to the kink in the seat stays. If I recall, at least one person had problems with cracks at the seat stay / seat tube junction on the BXT. I would worry about there here too because it is a light frame and that sort of design puts a lot more stress at that junction. The geometry looks good though.
I don't have any experience with spcycle.