There was a thread on this in 2010.
Niki Scevak recommended Earth Class Mail
Brad Kellet recommended MyUSABox, but they have had their domain name seized by USABox
Michael Guilfoyle recommended Usa2me.com
Earth Class Mail is now very expensive - $20/month + $5 for shredding + $1.50/page scan + ~$10 minimum to forward mail on +,+,+
Otherwise I'd go with them as them as they seem the most established.
Although, if their service is substantially better the admin time it saves is probably worth the $.