We have been using the mail service at Rainbow's End park in Livingston, TX for five years. We have had our mail forwarded many times without problem. The packages sent to us have always be sent USPS Priority mail except for one time when we had is sent by UPS. The last time we asked our mail to be forwarded, someone, without letting us know in any way, decided to send our mail via USPS first class. That mail has not arrived after a week. It either did not actually get sent or has disappeared in travel. The problem is there is no recovery. There is no tracking number. There not even any proof that it was mailed other than the deduction from our account.
I have since notified the mail service to always use priority mail. If you are going to use this mail service, then you should do the same. This will always make sure that you have a tracking number and can have some idea where you mail is. We do not expect to ever see the envelope mailed to us. You do not want to have the same happen to you.