Here's the scoop.
Once upon a time, there were two major manufacturers of toilets (and other plumbing fixtures, valves, accessories, etc.) in Japan: Toto and Inax. The Japanese, decades ago, fell in love with high-tech "bidet" toilet seats that use water to clean your rear end, and warm air to dry. Inax was actually the market leader, initially, in this segment when it was small. Inax was, I believe, actually bigger than Toto generally in Japan for porcelain fixtures.
The story of the market for automatic butt-cleaning toilet seats (and then toilets) in Japan is actually a famous case study in the advertising field.
Inax came out with a TV commercial for its bidet seat. It was very technical, oriented towards the device. I can't find it, but it showed the device itself at work, and candidly made it look weird, and made a lot of polite people uncomfortable even talking about the concept. Still, it got some traction.
Understand, of course, that Japan is a very formal and polite society, where women are expected to comport themselves even more politely than men. As an example, women were often embarrassed that someone might hear the sound of pee hitting water when they were urinating. So they would flush and flush and flush the toilet while peeing, wasting lots of water -- to the point that the Government embarked on an education campaign to try to put a stop to this practice. It failed miserably. Toto invented, therefore, the "Sound Princess" (Otohime), which makes a continual sound of rushing water once activated so that women don't have to run actual water to cover the sound of urination.
It became very popular. That's the society we're talking about.
Recognizing this, Toto's ad agency took a different tactic than Inax's when promoting the bidet seat. It used a euphemistic approach, starring a Japanese comedic actress of some note and undeniable femininity and politeness to explain metaphorically why a bidet seat was better than using toilet paper. You don't need to understand Japanese to get the point. Here it is:
149,000 yen, the price in the video, is about $1350 in 1990 dollars. Not a small amount, just for the seat.
The ad was a resounding success. People bought the Washlet in droves. Toto became the dominant bidet seat (and later bidet toilet) manufacturer in Japan, and ultimately the largest bathroom fixture company in the world. Biggest manufacturer of toilets anywhere, all under its own brand.
Inax was still very strong number 2 in Japan. And, frankly, its early seats were more advanced than the Toto ones. But, like VHS vs Betamax, it didn't matter. Toto had won the match.
A decade or more after Toto had expanded its brand all over the world, and had done a good job cracking the US market with its 1.6gpf toilets, which performed better than anybody's, Inax tried to enter the US market and to expand its brand. It struggled. Ultimately, it hired a guy from GE, who followed GE's conglomerate approach and started buying up companies that were a strong brand in their home countries. He formed a new umbrella company, called Lixil, and tossed Inax into it. American Standard was by then owned by a venture capital firm which had exported much manufacturing to Mexico and thrown quality control out the window. Because Inax had failed to crack the American market, Lixil bought American Standard and started immediately applying Inax engineering and quality control to its manufacturing, which turned out to be hard but which has caused a significant improvement over time. They also bought a bunch of familiar brands in construction, generally. Grohe valves in Europe. Some curtain wall manufacturer for high-rises, etc.
So nowadays, AS actually has a big force of Japanese engineering and manufacturing folks influencing it, as well as the influence of great engineers like those at Grohe within its ownership group.
Toto is selling thousands upon thousands of these expensive Neorest bidet toilets in the US each year. Not much compared to their volume of regular toilets, but at that price, it's pretty amazing for this American to contemplate. I am blessed to be able to afford one if I really wanted one, but I can think of a kabillion other things to do with that much money (including save it) that I would rather do.
Eventually, competitors had to take notice of this market. Hence this AS toilet that looks exactly like a Neorest but isn't, and is probably basically an Inax model in Japan that has been relabelled and maybe slightly-adapted for the US. Kohler has a similar one, too.
I can't see any reason why you wouldn't at least consider the Toto Neorest. Among other things, it's here to stay. Finding parts down the line for the other stuff might be challenging. You wouldn't want to end up with a $5000 Duchamp Fountain (i.e. non-functional toilet sculpture).