we are in the middle of our bathroom reno, and i had the same choice to make. we chose the toto aquia wall hung unit with the washlet s350e. sorry i can't post on the flush yet, but i was scared away from the duravit model by this youtube video that i linked below.

also, if you check the reviews on amazon for the duravit starck wall hung toilet, they are terrible!

also, toto is known for their efficient flushing so i decided to go with them.

Here is a link that might be useful: duravit flush

Thank you to Jackfire and naadimre for sharing their thoughts. I am going to look more seriously into Toto and ignore the comments about sometimes needing to flush twice. Apparently sometimes you have to with the low flow units. I am also going to look into the Inax advanced toilet seat as I heard that was very good and see if it can be installed on Toto products. I have seen a demo in a showroom.
I'll update when I have more information.

I have a toto wall hung toilet that is not installed yet. I have Toto Carlyles with one s300 and it is a great washlet. I plan to get a s350 to go with the wall hung. I have seen the duravit wall hung with the Duravit washlet at a local plumbing supply store. It is an expensive combination. I have not seen any reviews of the Duravit washlet so it is hard to judge the performance. The Inax looks a little bulkier on the toilet and not a lot of reviews on it throughout the web. One GW member has the. Inax and raves about it.
Although Toto makes its own wall carrier, it is compatible with the Gerberit in wall unit. I think Grohe used to have an in wall unit also. The flush actuators are only compatible with the manufacturers in wall units. One of the flush actuators from Toto was almost $400. I passed on that actuator.
Good luck!

do all of the bidets mentioned have theugly hose visable? are any conceled?

want to use with a toto wall hung and geberit tank.

Currently i am renovating a wash room with curb less shower with linear drain and wall hung toilet its very difficult to combine different products and plumbers are totally new to the concept in City like Toronto and the plumbing show rooms are also having staff that are not 100% sure on any combination as the product knowledge is very little. There is one model of Duravet where washlet seat and toilet is all concealed but plumber is not able to understand the assembly details and want 3 times the money to install. I will finish the wash room and give my complete start to finish project video. Share all experience of how it went.

We have used Geberit system and Duravit bowl and sensowash on 2 of our bathrooms and are extremely happy with them. Sometimes multiple flushes is unavoidable in my opinion

@needing_help12 what did you ended up doing it? I am on the same boat and looking for the references. Thanks you!!

We love our Toto wall hung toilet! We've only had it in use since March 2022 but so far it's performed perfectly and is super easy to keep clean!!

We had to plunge our 20 y.o. floor mounted Kohler toilet fairly regularly, but I don't think we've had to plunge the new toilet once. 

We'll never buy another toilet without heated seats or auto-flush. We live in Northern California (SF Bay Area) and love the heated seats, especially on chilly mornings. ;)

Thanks for sharing this.

Here is also Geberit + Duravit