Runspoonrun, why 3.15? to get a GFA for London or Boston or something, or you just being ambitious?
Brighton was 3h57.10 and New York was 4h02.38.
Funnily enough I am more than happy with New York as I hadn't realised my watch lost GPS a couple of times under the bridges and I thought I was in for around 4h20 so was just taking it easy with a view to enjoying the experience. So coming in that "fast" was more than a nice surprise.