Do yourself a favor and do not get a SERPA holster. With the caveat that I am not a firearm owner or gun guy, I have a buddy who is into law enforcement and I remember him laughing about this study:
https://www.fletc.gov/sites/default...g-room/training-information/holisterStudy.pdf
It's an interesting read, but it only seems to apply to the level 2 holsters with the release. What about the level 1 holsters that are devoid of the trigger release lever?