I bought this & installed it.  It flushes weird.  It doesn't seem to vacate.  (FYI, I've installed about 10 toilets in my life, & used hundreds).  

It's so bad, that I will rip it out and replace it with another brand tomorrow.

I've read the manual.  It says, "If you hold down the handle for more than ~2 seconds, air might get in and you have to flush it 5x to reprime the system".  REALLY?  We're going to expect guests to even tell us if the toilet isn't flushing right, and then we have an awkward toilet instruction conversation.

And, in 5-10 years, when you inevitably have to replace internal parts, forget it.  This toilet has 2 drains, not one, and an incredibly unique (they think this is an innovation, but it's a problem) system.  Instead of going to any hardware store, you have to order custom parts from this vendor.  Hope you have the part # & they are still in biz, and you get the right parts shipped since you can't just go to a local store!