Dont pay this guy ANY MONEY, look at his profile he has negative rating, he will bring you into confidence and cheat you after you pay him, please report him
Well, it may be checked pretty easy. Few guys seem to have their transaction accelerated realy. I sent with 278 sat/byte when it was fine, but got in 52-11-44 mins blocks in a row and now my transaction wont pass without acceleration coz for now fee is too low. So if it will, then this guy realy helping people for some reason.
Nope he cheats people by gaining trust and trying to sell bitcoins at a cheap price and takes money and stops replying, see his trust rating, whatever it is people use free accel service and claim they are doing it, anyway I am just warning you that this guy will cheat you if you pay him first, so dont pay him there are reputed accelerator services on the internet use them instead if you really want to pay.