As I understand it, there's no need to buy a 6G SSD since your bus can only run at 3G speed. OWC/macsales (who mayer linked to above) has well-reviewed SSDs, thinking of making this same move with my MacbookPro3,1. I do wish the product description for this made clear that the adapter is allowing you to put a SATA drive in a PATA bay--so your drive in the optical bay will run a little slower than it did in the standard drive spot. Might want to spring for the largest SSD 3G you can afford.