As much as I disliked for the most part the animation style for the cutscenes in MoF, Trevor's ending scene chokes me up every time I watch it. Robert Carlyle's voice on the line 'Live, my son....' Yes, I admit that I can be a bit of a softie at times.
I liked the game, overall. I just would have liked it to be longer, and have more enemy variety per area. My issue with the cutscenes animation was the weird, 3D pretending to be 2d-like style. The HD version was better with the inclusion of lip-sync, which was one of my issues.
Edit made for clarity.