We bought wide because the boat was to be our home and with a full time job, moored residentialy 90% of the time, the advantages of widebeam are just too great to ignore.
Four years down the line, having managed to make a (very modest) living from the boat and no longer tied to a land based job and residential mooring, we still feel the advantages of widebeam outweigh the cruising restrictions (we are in the South so have the Stort, Lee, London, Grand Union (to South of Birmingham) the Thames, Wey and Kennet and Avon to explore (yes we are frightened of he Severn).
Should this or any future government stop increasing the age for state pensions to be claimed and we are actually allowed to stop working and still eat then a norrow boat to eplore the rest of the system is very tempting.
Should any government (or Waterways Charity!) have the foresight and wisdom to remove the pinch points that restrict access for widebeams between the North and South then we'd keep the widebeam until we ran out of wide canals to explore (I do know that low loaders are available) but this would only delay the inevitable purchase of a norrow boat which IMHO must surely be the supreme vessel for serious full time cruising.