I also have a basting gun. It worked for a quilt or two, fixed it, got busy with another quilt - but then it broke - this time for good. Too bad, as I had purchased lots of the little tacks.
But I discovered spray and now I use spray exclusively. Much easier, faster, and gives a very much better sandwich.
Trying to locate all those little plastic tacks on the quilt sandwich after I quilted it was a bummer. Pins - not so good.