PayPal is a horrible system for people who sell software via the Internet. Their dispute policy favors the client with almost no ability for a merchant to dispute the clients attempt to get their money back for a product they received. Also, the fraud rate for PayPal is VERY high as many purchases are often made from accounts which have been "hacked". Coupled with poor customer service in the event we do have an issue with a customer, PayPal is simply an unacceptable choice from a business perspective.
WorldPay, and others, have significantly higher fees which are prohibitive as a source for processing payments.
Please do not PM me for support or sales questions. Thank you for your understanding.