I have an SPO1 shadow and use it in idpa ssp and uspsa production. I had Angus do a competition trigger job on it.
It takes some work to get it under the 39oz rule in ssp. My shadow weighs 38.9oz with plastic grips, smaller safeties, old style mag brake, plastic guide rod, and 10 round mags.
The easier option is the 75 Shadow. Weighs less due to the short dustcover. Starting seeing quite a few of them in both sports recently.