As usual Doug...we disagree, hehe!
I use Schallers on all my guitars, Firebirds included. You can get Schaller buttons from Allparts, even in bulk. While I've never known a Dunlop to fail per se, I have had them stick in the "on" position & have heard many horror stories of their button getting bumped, releasing the guitar. With the Schallers you have gravity working to keep the strap on & you have to pull to release, as opposed to push, which I think is more secure. I think an added plus is the Schallers buttons seem more secure when not using a strap with locks on it.
To each his own...as usual,hehe!
Tony