We have loops bolstered in a couple of places with snaps. +1 that the loops are preferable. Snaps are almost always difficult and sometimes bordering on impossible, while the loops work great even with thin gloves on.
In particular, we can secure the loops before zipping, which helps tremendously (the zippers get twisted etc after being rolled up). Trying to snap first, or to zip without having the ends tied down, would be much tougher.
The few snaps we have are in places like the lower part behind the transom door, where it makes things neater to snap down but is not essential.