Yes. And yes. You can also substitute the flapper that's in there with an adjustable one that would let you, if necessary, put more water into the flush cycle. If that becomes necessary, Toto will deny it but come back here and we will tell you what to do.
Generally, though, adding water to the cycle doesn't do that much in terms of waste removal, as I discovered trying to hold the handle down with my stupid Portrait toilet. It just ran more water in behind the clogged waste and filled the bowl. The key is to have a properly-sized and properly-designed trapway, which Toto does.