I agree with Worldtour that LWB bents are probably the cadillac of bikes. They are extremely comfortable, have almost no learning curve. ride great.
Downsides - longer turning radius, a bit heavier and longer to transport, but these are all the possible negative things I can think of. None are a big deal at all.
LWB bikes are reasonably fast with the average rider, but their claim to fame is more comfort than speed, although they are sure no slouches, either.
All bikes are great and we all have our favorites.