I have been looking at some radiant hydronic wall units (is that just a fancy way to say wall mounted radiator?) to use upstairs instead of baseboard and they look like a good idea. Brands were Buderus and Runtal. Anyone out there used either one? Comments on performance of this kind of unit? I am also scrounging for used old cast iron floor radiators but I am not sure the chase will be worth it in cost savings over these wall units. One concern is how hot the water has to be to make them work. Nick R.