I’ve never run a Glock 18 or 93R but have run a 17 converted to select fire (so basically a Glock 18)
I can see it’s use in a very limited usage envelope. With SHORT bursts it’s not all that bad but it’s easy to get away from you.
Like has been said I can see any of these being fairly useful for discrete body guard type duty. They are a perfectly fine Glock 17 if needed. However if needed you can slap a 33 rounder in and drop a quick wall of suppressive Get the hell out of dodge wall of lead.
Again their real world use is fairly narrow.
They are however a fantastic way to turn money to noise REALLY FAST. like make an MP5 feel semi auto fast. I like noise.