I have an Explorer XS and they are great detectors. The price on used XS's are a real bargin and you have on of the best all round detectors around.
The best advice I can offer you is to get the book Mastering the Minelab Explorer XS & S, written by Andy Sabisch. It is a great book that will you understand the Explorer, I have read the book at least five times and learn something everytime I read it. Read the owners manual and follow the instructions of Andy's book to the letter and the Explorer will amaze you on what it can do.
I used Andy's program for hunting jewerly on the beach at a local park and found a real nice gold ring with-in the first 15 minuets. The Explorer ignored all of the trash and hit solid on the ring, Thanks Andy.
Good Luck, and Happy Hunting. TB