I want to purchase winamp pro
 

I want to purchase winamp pro, but I want to know how long the license lasts and if I will be able to get the newest versions for free.

I bought nero 9 and two months later a new version came out and they told me if I want the new version I have to pay again. So I will never be making that mistake again...

If you pay for Pro, you will get any 5.x update for free. The pro key is still valid for early 5.0x users and that version is many years old now.

But if the key will still work for Winamp 6.x (whenever that will come), nobody can tell you.