I'm sure this will turn into an informative thread!!!
I think that if they're done correctly, neither is "easier" The snap in's should be safety wired once installed, so that pretty much negates any ease of removal since you usually have to remove the seat to get to the sub straps to remove the wire (unless you're a contortionist with very small hands).
Most bolt ins I see are angled wierd and not able to articulate (kind of early so excuse me if that's the wrong word for what I'm trying to convey).
I usually remove the hardware for the shoulder straps and go for the wrap around style. 3 less things to go wrong (no bolt, clip or bracket).