The factory speakers in the MG4 Xpower do produce a descent-ish sound, but I find the sound muddy and the speakers inadequate, especially at higher volumes.
The stock speakers are 25W and become uncomfortable when doing 70mph. The speakers are moulded and glued into the mount, so it's all in one. I couldn't see any after market mounts that I was comfortable buying, so I found a model here and printed my own using ABS+ filament.
I bought 2 pair of JBL Stage2 65CF which are 90W RMS at a good price from Amazon.

in progress