Ive made up some rigs for trolling where i use a large size on about a 3" loop about a foot up from where the casting sinker is.
Sorta like a drop shot rig, but when i ran out of them i used a small coast lock snap which seems to work just as well on the fish and is far less costly.
Ive not tried them for just tying on a single jig and have been using a small loop for that also.
But I'm going to try it due to the easy ability to change the jig. Figure on using needle nose pliers to get hooks or jigs off easier.
The Bass Pro in Palm Bay has them in the fly fishing section for about 12 bucks for about 20 of them, which is about 3 times more than the coast locks. But they are much smaller and would be what id try first for a single jig.
But id recommend picking up a pack of the smallest coast locks they have also, or you could just cut the swivel off of a very small snap swivel.