Tube Pre/ Class D Amp - Who has done it?

@marco1 I definitely am not missing the heat. I was very particular in getting rid of heat generated anything and am limited to my Allnic now. But I can dream. 

I've been running a tube preamp with class Ds as well. Both are balanced and the amps are so light and make no heat so they sit on top of my speakers. I'm able to run long interconnects so my speaker cables are quite short. I used to run a set of our M-60 OTL monoblocks (fully optioned) but the class Ds do everything better so I don't miss the tubes at all (although I enjoy tube amps quite a lot). Nice to have no heat even after running all day and no worries about power tubes while having the same relaxed mids and highs.

AGD Audion mono blocks with an Ayon pre. Great combo. 

I’ve run various tube preamps into Class D amps and consider Class D just like any other solid state amp wrt compatibility with a tube preamp or linestage. 
I had the matching set of battery powered pre and power amps from Veloce Audio (LS-1 pre and Saetta hybrid monoblocks with 6h30 tubes and Hypex power module), also run tube preamps with PS Audio M700s. Never had an issue. I think Class D has come a long way since the early days. I’d like to try a GaN Class D next up, maybe one from Atma-Sphere. 

I have had my Canor Hyperion P1 Pre paired with most of the AGD Monos and also a VAC Master paired with AGD Duets specifically driving some Cantons. I have also used NAD and Primare Class Ds with the Hyperion.  All of the combos were excellent.  

Like any preamp, amp combination you need to look at the impedance, gain and voltage to make sure the equipment is matched well.  If you have a good match, it will sound great assuming that sound profile meets your needs.