- VAIO Z uses a custom optical Lightpeak version. The current copper Thunderbolt implementation of Lightpeak doesn’t have enough bandwidth.
- You need a separate power cable for the “addon”, and very likely another power supply for it. Current Thunderbolt external graphic card solutions ( like the Silverstone T004 ) have another power supply inside the case. Not very efficient.
- PRICEPRICEPRICE. Come on. It’s a PRO machine. Looks are not important. Price is. Custom parts for the Cilindrical Mac Pro + Custom External devices/cards = $$$$. They would be custom made for it, so expect a very high price. And for pros (remember, they are the target market) it’s normal to update graphic cards every year, and even more frequently. Most likely they will try to avoid a machine that requires a special ultra-expensive version of the same part available for other computers. It already happened on the past: a lot of Mac pro users switched ~10 years ago to PC for this very reason.