I still have an old-school EBMM gigbag (I think they were made by Levy's.) it's shaped liked a rifle case.
I got pulled over once on the way home from a gig, late night (Bogus ticket btw, "rolling stop") the Officer got sorta jinky when he saw the bag in my back seat! I explained it was only a Sterling!
I also had the original plastic material EBMM HSC, I believe it might have been made by SKB. I left it in my car's backseat on a hot afternoon, it actually got a melt-down crease in the middle!
So even if a HSC is a G&G or equivalent, IME they still are not practical. If you are going to travel by air, an ATA is the only real answer, and if you're playing local or for most cases, a good gig bag does the trick so long as you don't bash into anything.
If MM is providing a lower grade Mono bag, so be it.. I had a Mono M80, and although it's a great bag, it's a bit overkill IMO. Padding & storage are all good, but a basic gig bag will do the job if you take care.