Not even going to get into which snap and swivel combination is the best, but for today, just looking at the different types of snaps that work best in certain situations. It is not really all that complicated of an issue. Which works for me today, because having walleye for lunch in the shop while its raining, and time is of the essence.
The two most basic types of snaps are of the Cross Lock and Duo Lock varities. Now there are company variations on the spelling of each snap, like when Berkley call the the first one their “cross-lok” snap. Its a good snap, and really the strongest of the two, but will not work the best in all applications.
The sharp bend in the cross type snap works best when using line that has knotted in a loop. It can be with regular mono, or with wire like with a leader that one would use for fishing pike or muskies. This type of snap also works well with divers and inline weights.
The Duo Lock type snap has a very pronounced round bend in the snap section.
The round bend makes this snap my choice when running crank baits that depend on some type of wobble action to call fish in to strike. Think of it as a metal version of the Rapala Knot. Instead of having the wire come to a sharp point like bend, the Duo Lock will allow the bait to slide side to side, giving it that critical life like appearance in the water.
You can definitely go with the Duo Lock snap for all applications, but you cannot go with the Cross-Lock type in every situation. Having an assortment of each really does work the best, but in a pinch, just having the duo lock will not hinder your fishing experience.