The pd gt is more solid and has less vibrations on mishits. I have. 2 and they are 3 grams apart. Both balance the same when matched with lead.
I prefer the pure drive on serve..it just hits so big. I also am able to hit flatter when needed.
Watching mike russel warm up with his pd. he and I are the same size and age..I'd love to see how he specs out his babolat. I would bet he uses the +.