QUOTE (bobD @ Aug 11 2008, 1:48 pm) 
I favour the Rotterdam - Hull route, the only issue being the times (21.00 only)
I took the Rotterdam (Europort) - Hull route a number of times in the late 70s/early 80s when travelling between Hamburg & the Manchester area.
Big ships (got bigger since), pretty stable in rough conditions. "Fun" during the Falklands when one of the ferries got send "South" and was temporarily replaced by a smaller Finish ferry - and in the roughest weather. Interesting crossing.