Did you read in English? I read it in french and loved it, then looked at Montcrief's translation - I would not have made it through. Montcrief turned Prousts clear and precise (but long) sentences into a kind of esoteric word puzzle. Lydia Davis' translation looked much better.

For War and Peace, I didn't know russian, so I tested different translations before going ahead. The translator makes a big difference, I found some translations hard to read.

I had your feeling with Ulysses, though. No translation issue there. Couldn't make it very far.