As a guy I find both incredibly sexy, but it really comes down to what you believe is best. Go with what you are comfortable in. That is the only thing that matters. Enjoy life.
Love the scrunch butt bikini's can almost get away with wearing them at the public pools near home. Only get a few "hussy" looks from the moms. Now the Thong bottoms I love them too but only for vacation or private pool parties. So whatever you are comfortable in.... wear them.