Yes, with the Nice PayPal Downloads you can limit the buyer by the length of time that they are allowed to download a file, by the number of times, or both.
I use the Nice PayPal Downloads extension on my site. So, if you are looking for something that works the same, look no further.http://trinitronic.com/index.php/Downlo ... loads.html
Let me know if you have any other questions.
~ All the best