Very useful links, thanks again! So both flights arrive/depart T5. If on time, 3:25 layover for the first CFU option and 5:25 for the second I suppose I can be really conservative and go with the second and have plenty of time to spare. I can't imagine baggage claim, customs/immigration, checkin and security taking longer than a couple of hours... tops. No? Seems worth it for the savings.....

DEN-PHL-LHR-CFU