Well, we've wandered off the subject, but....
The Sprinco unit is gone along with the one I bought for my Super Witness. Both of them made the slide so stiff that it was nearly impossible to lock it back by hand and totally impossible to release with the slide-lock lever. The Sprinco units were so stiff that they battered the slide-lock levers to the point where they had to be replaced.
When I went back to Wolff springs the Super was fine, but the .45 has never been reliable. I replaced the mag springs, too. Better, but not good enough that I'd trust it for carry.
Sprinco has an excellent warranty and will honor it. Good people to deal with.
Anyhow, does anyone have experience with the compact poly .45 Witness?
John