Had a good look at one of these today, in Red with some sort of racing stickers. Under the targa roof panel there is a sticker saying you must not drive above 93mph with the roof on!
Seems that recently there are almost as many 599 GTOs as standard 599s. There were at least two 599 GTOs at Brooklands on Sunday, a blue and a deep red one. Saw a pair in showroom at Ferrari Egham a few months ago, both 'chavved' up...