marc, glad to see you had second thoughts about getting your back up.
As flying at night in the US is an absolute delight, it is well worth paying an instructor over there to gain the qualification and the experience. Think of all those instrument approaches you can do without extra fees. Think of turning on the airfield lighting yourself, by just pushing the PTT. Think of landing at Key West by night.
Also, night flying has the advantage of fewer idiots floating around getting in the way.... just you and an enroute controller who actually has the time to talk to you. They welcome light aircraft in controlled airspace, as they know who you are and what your intentions are.
Enjoy!