Imagine having a trem that does none of the cool stuff a Floyd or even a vintage Fender will, now make it so you can't adjust any tension, and make it so that it will ONLY float. Seriously, going from standard to drop D will throw it out of tune.
Oh yeah, add a bridge that pivots back and forth, as well. Fender Mustangs are total pieces of sh*t, from the bridge to the pickups to the controls to the short-scale neck.