When designing iD4 we wanted it to work with as many systems as possible to make sure it was a complete versatile recording interface. USB 2.0 was chosen as it is currently the most prolific port on computers. This means you can use your iD4 in the studio or out on the road and not have to worry about finding a compatible port.
But isn't Firewire, USB 3.0 or Thunderbolt better?
It is true that USB 3.0 and Thunderbolt offer higher bandwidths but iD4 simply doesn't need the additional bandwidth that these connections offer.
Currently, Thunderbolt is only available on Intel motherboards which means there are many computers out there which are not compatible with Thunderbolt and will never receive support for the format. The USB 3.0 specification requires complete backwards compatibility for USB 2.0 so even if USB 2.0 falls out of usage, USB 2.0 devices such as the iD4 will still continue to work and you will still be able to record groovy tunes.
We thought that this was the most important thing when choosing which connection to use and we believe we made the correct choice. When you are on the road, you never know where you might end up and using USB 2.0 means you never have to worry about finding a compatible port.