I did not expect much from a system on a $22k car, but I do feel like they could have done better with the sound quality. It sounds to me like they don't have the speakers aimed at the right positions. The sub can be quite a surprise, though, when given the right song with some deep bass.
Coming from a 2001 Audi S4 with Bose system, so there was a lot more mids there.. "no highs, no lows.. must be Bose" ;) I feel like the Focus could use a bit more oomph in the mid-range, even when I adjust it, feels kind of lacking.
Am I going to replace it or modify? Nah. =/ I am more concerned with the subpar antenna that came equipped. THAT I will likely replace.