Do you have "Ignore Unencrypted Peers" checked in your torrent client? (I know this is an option in Transmission). If you're blocking unencrypted peers (which is a good privacy feature!), or behind a firewall, I believe you'll receive less connections, which can affect your uploading.

I bought an account here once—it was fine, nothing bad happened—no credit card info stolen, etc. It went through and I had access to the webcam recordings  ;D  If you're worried, though, why not buy a prepaid credit card?