Difference between 2 Premium keys:
1 Year Premium Key can be used for one year only.
The activation period starts with the first activation. At the end of this period the license will expire automatically. You're not obliged to purchase the new license. it's up to you to decide.
The Unlimited Premium Key works as long as your PC 'lives'.
If you decide to format your PC, you need to contact our support team. We'll reload the key and you'll be able to continue using it.
Both premium keys can be activated on 3 different computers.
It's a One-Time Payment, this means that you pay only once after you've chosen your Premium plan. No recurring charges.