there are lower(cheaper) models with the same features. you also get dect repeaters for additional coverage from the same manufacturer.I will be getting a w60p, but the concrete thickness and distance between where the base will be and the upstairs area concerns me. Not sure is signal will be strong enough. Might have to get hold of one of the local VoIP providers to demo a unit for me, so I can see if it will work.
usually dect coverage is pretty good though so repeaters are not always needed