My only complaint about 100% VG is acne. I vaped almost exclusively 100%VG for most of a year and had horrible acne, which has only just started clearing up since I started vaping juices with a little PG. (I don't think this is an "average" reaction to VG, I just have very sensitive skin that's prone to breakouts.)
Vapor, throat hit, and flavor were all great, though. Some of my 100% VG juices just needed to steep a little longer than those with VG & PG.
EDIT: I just saw the bit about the film and coils. I only have coil issues when I'm vaping VERY dark liquid (almost black). As for the film, my husband's windshield in his car has way more film than mine did (he's a smoker), but mine does sometimes get a little bit of a film on it.