If it's anything like my old French version, I wouldn't recommend it. I bought the french version at retail many years ago and then proceeded to discover that the translation is actually incomplete.
There's some missing text at some point in the game, and some dialog is still in English. It's too bad really, because the french version is otherwise actually good. They've done a pretty good job of translating the colorful vocabulary of Sigil's inhabitants and the VA isn't too cringe-worthy.
Maybe a patch was eventually released to fix the translation, but if it wasn't updated then I strongly suggest sticking to the english version.
Post edited September 28, 2010 by KingOfDust