Of course no customs are involved with domestic.......as anything that is already in the USA has alreay went through customs once already when it came to the USA......
Thats not good advice bro.... USPS is always the way to go.... Fedex, Ups, etc. can open your pack up for no reason at all.... I've never dealt with a domestic source that uses private couriers
I've used both - foreign and domestic - no problems either way but I prefer domestic - if you got shit for a source you may have problems - have never had a problem with a source that was recommended by a mod