USB3 HDD on an USB2 port vs thunderbolt I need to buy a new HDD (>2To so no SSD solution, unless you know a very attractive offer) and I was wondering about performance knowing this :


MBP 2011 (2 usb 2.0 - 1 Thunderbolt);
7k2 HDD.


What would be the fastest solution : USB 3.0 on an USB 2.0 port or Thunderbolt (HDD speed is around 100MB/s) ?
A USB3 connected to a USB2 port will work as fast as a normal USB2. 
With USB2 you'll get ~40Mo/s, with Thunderbolt you'll top the write speed of your HardDrive. So if you want speed, go Thunderbolt !