Some of my favorite hops combined with a terrific base malt. You cannot go wrong with this combination. I like to mash the Maris in the low 150s as enough malt sweetness comes through by itself without having to rely on longer chain dextrins to fill it out. Challenger and Chinook are typically used as bittering hops but as the last poster said, doing the reverse is very viable. I love me some EKG. Love the aromatic components. Definitely an end-of-the-boil kind of hop for me. For the chinook and challenger, I'd do some of each in the boil and flavor additions. Chinook has something to offer for hop flavor while Challenger has always been a great hop for bittering English beers.
English pale / IPA / bitter / whatever STAT!