I know they have hired a lot of new instructors I hope this is not an indicator of where they are going. I will be taking my SERPA holster and I guess a spare holster now. I have never been to a firearms class where the instructor did not say something that was incorrect, that is simply mind boggling for me.
You don't even have to be in a class to have an "expert" espouse some BS they have no clue on.
I was in one of the local ranges and the "resident expert" (an employee) tried to convince me that the SERPA holster had a fatal flaw. He said that if one were to pull first on the weapon, before actuating the release, the firearm would remain locked in the holster while your assailant "shot the $h!t out of you".
20 straight successful draws from mine, while tugging so hard I almost gave myself a wedgie, and he changed the subject.
No matter what the holster, manufacturer, material, angle, belt attachment, there will be someone that doesn't like it and there's no reasoning with them. Ignoring works best. Keeps the blood pressure down.