What kind of bikes are they (the one you'll be riding and the one you are riding now)? It's probably fine to pick it up when you get there and spend a few minutes dialing it in if you are riding a similar style of bike - maybe get the guys at the shop to give you a quick fitting. Sounds like more trouble than it's worth to ship it home and back, but you'll need to make sure that you take it slow at first on the new bike and adjust things when needed.