[masraum]

This is quite interesting.

From a thread on the miata board.

eiichi Tsuchiya (of drifting fame) drives both cars at Willow Springs with interesting commentary.

Part 1: http://www.youtube.com/watch?v=vRARVVmpzTw

Part 2: http://www.youtube.com/watch?v=O_d5-K109DQ

Cliff Notes (for those of you who don't want to watch): Solstice is cheaper, faster and easier to drive.

Another quote

It seems that his biggest complaint is gearing. (He didnt operate the top nor transport luggage during the test )

According to Car and Driver, the gear ratios have been adjusted in both the GXP and the base Solstice. Third gear is not as tall as it was.