jgarzik: I don't see the option on the site. I emailed them though and got this response:
Dear Customer.
Thank you for contacting Liberty Reserve.
Liberty Reserve Premium is not real, Never assume that if a particular website has the words, "libertyreserve" in its name, for example, "libertyreserve-profit.com", it has anything to do with, or is endorsed by, Liberty Reserve.
Walter Tripp
funny since it is their blog...
idev & Drifter: thanks these seem good. I had only looked at that bsrates.com site and all those charge a lot.