In this country, they are new.
Up until this point, water hadn't been an issue either.
That is changing though.
There is only so much water, and there will more and more people.
I've been selling the dual flush units for years now.
Starting with the Caroma dual flush, of which I've sold quite a few. 28-1/4" long for the round front.
Toto has a nice dual flush, elongated bowl and very compact at 27-1/4" long
Gerber has a Sloan Flushmate model with dual flush too.
Any of these three models would be a good choice.
All of these sell for more money than the standard toilets.
So it does cost a bit more in the beginning to save water.
It does pay in savings later on though.