My house has hot water baseboard heaters behind the toilets. The radiators extend about 3" out from the wall and stand 8 to 9" high. The 30 year old Eljer's had plenty of room back there, but looking at some of the highly rated new toilets I don't see enough space for the heaters. So my questions are:

1. Which highly rated toilets will leave the most space for the heaters?

2. Since the new toilets will probably be closer to the heaters, should I use waxless rings?

TIA for the advice.