mhwolf but I want a rotary pump
I thought this might have been your requirement. And you are right, there aren’t any espresso-only capable machines, or SBDU machines out there equipped with a rotary pump.
If you want finer temperature control and a rotary pump, you might want to consider a dual boiler machine and run it with the service/steam boiler off.
There aren’t many non-commercial videos of this machine out there. There’s this one:
Gives you a good idea of how the machine operates. Of course, take it with a pinch of salt as he might not necessarily be running the machine exclusively in BC2 mode or how you intend to run it.
I actually had the opportunity to see this machine in person and use it, and have to say I’d strongly consider if I was in the market for a new machine. Depending where you are in the world and what you want, the Lelit Bianca is the rival contender for a lot more features (flow control device, programable slow/hight flow settings, etc), dual boiler, albeit a little more expensive out of the box.
Good luck!