Yeah, it's disappointing that Fiat's quality is still pretty poor, because they import an interesting, relatively economical product that I'd seriously consider buying if this rental experience didn't sour me. The little thing was a BLAST to drive, even for a 1200 mi each-way trip. This is one car that I'd think about leasing, since if it died a year after the lease was up, it would be Not My Problem(tm).

Transmission issues are fixable by ordering a real manual, but starting issues and brakes simply should not happen with such low mileage. Even in a rental. Also, interior materials seemed flimsy, borne out by further research:
http://www.fiat500owners.com/forum/10-fiat-500-appearance-body/5021-armrest-failure-point-discovered.html