Thank you very much for the warm words and for using WinMiner 
PayPal fees vary by country and always include an additional fee for international transfers.
For example, see a quote from the US site - 
"In the U.S.   a fee of 2.9% of the transaction amount plus a fixed fee based on the currency.
Outside the U.S.   a fee of 4.4% of the transaction amount plus a fixed fee based on the currency."
WinMiner goal is to max our users' profits - if you are aware of a good, cheap global method of payment, do let us know and we will gladly look into adding it.