I'm not sure that it's possible to definitively rate one manufacturer's generic over another's, since people often seem to get results/side affects that are unique to their own situation/makeup. Whilst there are certainly going to be differences between the effective manufacturing/ingredients (non-active, especially) between the patented drug & different manufacturer's generics (and arguably between different batches from the same manufacturer over time), the only thing you really have to go on, is personal experience.

FWIW, I've used generic fluoxetine from Walgreens & Walmart (Teva) & not experienced any noticeable change in experience between them.