ok so all this talk about magpul class got me thinking
which is the best system for classes only?
i know you're supposed to train how we carry, but since we cannot carry here, what is the thinking?
i guess if one is going to do gun gaming, OWB is better, but am i overthinking this (as i always do)?
This question came up in an "Ask the SME" thread a while back on M4C. It will likely depend on the instructor and how comfortable they are with your firearm handling skills. At the basic level, they probably want to at least be comfortable with your handling skills before they let you run concealed. Running your guns in OWB allows a quick glance to check the condition of your firearm.
I took my RCS holster and even an AIWB holster to my recent handgun class, but it was so damn cold there that I didn't even bother trying to run concealed. The instructor did go over considerations for carrying concealed, like garment restrictiveness, layering, etc (all of which didn't really apply to a hot climate like Hawaii).
In any case, be sure you use your gear to try to shake out some of the issues before you get to the course. You can do that through dry fire, draws, etc in your home if you can't find a suitable range to try out your gear before hand. Before the handgun class, I added a grip plug to two of my Glock 17s and it ended up causing a problem with binding magazines, not allowing them to drop free upon reload drills. I should've tested it out before hand, but I didn't have time and figured what harm could a grip plug do?