If you have to stop in Canada don't forget to call them ahead and give them your ETA.
If you are delayed and your ETA in TEB changes significantly get dispatch to call customs and advise them about the delay. Both Canada and TEB get really angry if you don't advise them about delays or arrival.
I higly recommend Atlantic Aviation. But first you have to park your airplane in front of customs - the crappy old building just left of Atlantic. DO NOT open the door unless a custom officer stands next to the airplane. Atlantic will tow you after you have left the airplane.
Get used to many different call signs including every letter of your call sign and the aircraft type. They don't use standard phraseology.
If you spend a couple of days in TEB, why don't take a hotel in Manhattan. The SAS Radisson (Lexington & 47th) has good rates. The limo drive costs about 150$ per leg.
Enjoy!