When I had my 3 toilets replaced a few years ago, I chose Kohler water saving toilets. They work great, no issues.

I think you are correct, clogging can happen because the water doesn't move from the tank to the bowl fast enough - usually due to lime buildup.

If you are replacing, consider the height - particularly if you are older and don't have small children in the house. The taller (comfort height) make a big difference!

I have the Kohler Memoirs Stately - got them from big box. Great flushing also.

We are older! Good points.

I also replaced an older toilet - well water. I got the Toto double cyclone flushing. It is excellent!

@Stax - I understand where the lime builds up... and one may-or may not- be successful at cleaning the passages by manually clearing out the holes under the rim. It's not worth it on a toilet with 30 years of buildup.

If some of you "older" people are short, consider leaving at least one old-fashioned low toilet. :)

"Comfort" height my ***!