phil , the 220 is a good unit but if you want to listen to the comms you will have to use a bluetooth unit.(unles its in a car mount.)
it can be used hand held as it has a built in battery and speaker.
its smaller than the 660 and is restricted with power. its supply comes from a mini usb socket on the back , good in the car but imho piss poor on the bike having to fiddle about.
if you want a good all round unit for car bike and pedestrian i do believe the 660 fits the job perfectly but you will have to stump up some more readies!!