Since this is essentially a shareware product, wouldn't some service that handles all those options for you be better, like BMTmicro and Fastspring? These also

Since this is essentially a shareware product, wouldn't some service that handles all those options for you be better, like BMTmicro and Fastspring? These also handle hairy stuff like VAT MOSS for EU customers that -AFAIK- Paypal doesn't handle for you and you have to it yourself.