It's certainly easier to clean under them. Be aware that you will need to have additional framing in the wall as well as, I think, re-plumbing the drain line.

HERE is correct. There is a considerable weight load that must be supported from the wall behind the toilet. In a typical wood frame construction as is common in Canada, you will need to beef up the wall structure to accommodate the toilet. Often, to accommodate the drain, the wall must be made thicker. With conscious design, this is an opportunity for a shelf or other concept to disguise a plumbing necessity and create a decorative feature.

Villeroy & Boch has an amazing dove grey stone suspended toilet, and of course there are many options.

Just don't make friends with large people. Sad but true. New standards in the US (for commercial interiors) are requiring floor mounted toilets due to the dangers of excess weight breaking the toilets, or pulling them off the wall.

Had wall hung toilets in commercial properties, and given the myriad installation and maintenance costs associated with them, would never do these in my home. You may like the look, but I'd rethink this. Sleekly designed, floor mounted, low flow toilets are also readily available. I'd go that direction.