If anything, I think maybe 8C would be appropriate (Extra Special/Strong Bitter), although at 4.1% you could probably swing 8B.
I've never had the beer, but everything seems pretty OK for that style. It uses pale malt, crystal and a little black malt for color, which is OK by the guidelines for either style. The IBU is technically in range for either style, although nobody actually tests IBU, its more about perceived bitterness. ESB can go up to 50 IBU though. All English Pale Ale/ Bitter styles are allowed to have American hops and American hop characters in the aroma, flavor etc as outlined in the guide. The english yeast should help with he character too.