I really want to like this flux chassis but no - FLUX DEFENSE Raider 365 Ultralight Carbine Conversion

I really want to like this Flux Chassis but NO. I have had problems with this set up since it arrived. First, my factory 17 round magazines work most of the time (They don't always drop free though). But, I wanted this chassis with the option of carrying 21 and 25 round magazines. They don't work. Neither 21 or 25 round magazines will drop free. The drop free is supposed to be a key feature if you want to grab the magazine in front of the trigger guard the mag in the grip is supposed to drop free. It never does. Also when using the 21 and 25 round magazines the slide stop lever will not push down to let the slide forward. The slide stop will work with the 17 round magazines though.
For almost $400 I would expect a little better....