I suggest you continue with whatever you have been learning up to now, British or American English, for consistency. If you are travelling to Europe and the United States, either form of English will be understood. If you're intending to live and work in Europe and United States, I would have a different answer :)

British English will set you apart from the many other Chinese students. As an Englishman I'm often delighted that just having an English accent is all that it takes to make friends easily in America!

No doubt it is better if you learn British English, but I suggest you to start first with American. American English is easier as a beginning.

Since I'm an American, I would suggest 美国的..... just kidding. I would not get too worried about this really. Focus in on learning English period - some of the difference aren't that great..... qu nar or qu nali ;-)