The
Kohler Santa Rosa works pretty well, I have a used one in the garage right now that I pulled from a home setting in a box. They went with two Ultramax with CEFIONTECT, first one, then six months later another one.
I don't know much about the Sonoma, but it should work.
I wind up being a little careful, it's better for me to sell somthing that that I trust I don't hear back from about, it always feels a bit chancey otherwise. I used to sell some $99 toilet that worked fairly well, they weren't perfect, and that was the problem. They had some tank wobble, and really it didn't matter, but it did to some. Whe the rep told the customer that their product shouldn't do that ( and he went out there to the home and did his best too) I decided that I would drop the product line. His loss, not mine. My sister has a couple of that brand in her home, still going strong, and they don't care that the tank moves a bit.
Her kids have ruined a few other brands over the years. I give her stuff, her kids wreck em. and then she gives me the report on them.
Very good information that the reps never tell you.