You should have done testrun with an izzi agent before subscribing.

I am not sure. As I know, the difference between Izzipro & Izziyou is their ability to receive signal. Izzipro is stronger than Izziyou. Speedwise, it depends largely on the area you resides. If your area is congested with many Izzi users, then you might get tortoise speed even though you use Izzipro.

I may be wrong, so correct me anyone....