I've had my fair share of mech box problems with my Ares M60E4 over the years. they were all fixable with the use of generic parts.
finally broke a proprietary part the other day.
its a small plastic piece which holds the spring guide in the mech box. this lever allows for quick spring changes.
the contact point it makes against the spring guide is no more than 5mm
thought about contacting Ares to get a replacement part... but decided not to since it such a poorly designed part that would eventually fail on me again. also with all the comments in this thread i think it would probably take weeks to get the part (if I'm lucky)
I decided to fix this crappy / flawed design with a piece of wood I found in the dark corners of my basement.
tested it with modify m120+, m130+ and m140+ springs.... it works....
on top of that I still have the ability to preform quick spring changes...
.....so there you have it.... my Ares m60 mech box is being held together with a piece of wood I found in the dark corners of my basement which works better than the proprietary part it came with....