The one next to Rub A Dub just off Jamaica Street used to be a fair price and nothing fancy.
A bit further away, across from Argos there's another that I was charges 12 quid for a short back and sides in. He also did the wax up the hooter thing for nostril hair and didn't charge any extra.
Not sure on the names tbh, think the Argos one is Kings Barbers.