I guess it depends on how comfortable the OP is when it comes to getting around. I first went to Japan by myself as a teenager and found my way to Ebina station with no problems. After all, there were plenty of English speaking personnel at Narita along with tons of signs.
Either way, he'll have to face the crowds and learn the transit system at some time during his visit. Might as well do it in Narita with an English speaking transit worker showing you the procedures.
Just my opinion of course.
