NEW Thin-Client recommendation

Good day

One of our customers has bought WYSE Thin-Clients (Model No: Dx0D) and is not happy. Although WYSE belongs to Dell the support is horrible.
They need it for conference / meeting room‘s. If you need more information please see my other question:
https://community.wyse.com/forum/showthread.php?27247-Thin-Clients-with-SCCM

We need to integrate the new Dell Thin-Clients to the Domain and use a Single sign-on login to Citrix. We would prefer if we can install the Thin-Clients with SCCM and integrate them to WSUS.

Do you have done already a similar evaluation? Can you recommend any good Dell model?
Any post is much appreciated.

Many thanks advanced