I've been using them for a few months. They're ok so far. If you have an 'issue' it is better to call in and deal directly with a person than to do the email thing.
Bear in mind the limit of the number of pieces of mail you can receive in your pricing structure, and realize that if you've filed a change-of-address and junk mail gets forwarded you're going to have to pay extra for receiving that garbage.
it will be difficult to get my mail out of the Earth Class Mail System since USPS does not allow mail to be forwarded from commercial businesses like that
I've been up against this too, so yeah, it is possible to lose touch with people (or vice versa), On the other hand, you purge the junk mail chain that's been following you around. Most personal contact is done via email these days anyway.