Daniel, great to read this! I'll give it a try.

Last question: I only would use this very portable host for recording the physical Ins of the UCX as "raw audio" to a fast SD-Card. My preferred Recording App would be DigiCheck with it's Global Record function as a very special kind of DuRec for UCX. Could this work (up to 192kHz) in a stable way? Do you (or other users) have any experiences with it?

Have not really tried Digicheck with these tablets. Concerning portability of that Micro PC, the extra monitor might limit that somewhat, won't it?

Regards
Daniel Fuchs
RME

Meanwhile I did many tests with a different Mini PC

This one is bigger than the first (about the size of an iPhone 6plus), but has several advantages over it:
- aluminum housing (with additional cooling effect)
- inbuilt battery
- 2 USB ports 2.0
- 2.4 + 5 GHz 802.11 a/b/g/n WiFi (although I only get 20 MHz instead of 40 MHz bandwidth at the moment)
- 64 GB Harddrive in 2 partitions (Win 8.1, Data)

I am enthusiastic! This small and cheap box works excellent with TMFx and Digicheck without any restrictions. The whole system is fully controllable over a single iPod Touch (direct via WiFi or Ethernet), no external display, no router is needed. TMFx + Digicheck with up to 192 kHz meets iOS, with DuRec for BF and UCX inclusive (iOS devices can be charged while working) You can switch over from a desktop remote app (like IIParallels) to TouchOSC or other controller apps with one device (Android should also work), all works in conjunction with each other, great!! The system is scalable for individual needs in a very efficient way. Of course you can also use it in "normal" environments with a computer display ( 1920x1080 over HDMI), mouse and keyboard (wired or wireless) and several independent controllers, but I was looking for a most compact field recording solution as small as possible but without any technical limitations. The inbuilt data partition saves 18 UCX-inputs at 44,1 kHz as Multitracks with a duration of about 3:30 hours. A high speed microSDHC could extend the space (but I did not test it for direct recording). With the highest bitrate of 192 kHz and 12 physical inputs you can save about 1:15 hour - no external USB drive is needed (although you can use one or even more to extend recording time). My tests over several hours did not indicate any write/read errors. The system is solid and stable, no crashes or freezes. I think it is fully suitable for different kinds of Live Events (with additional hard-/software-controller over MIDI, Mackie, OSC, BRC, ARC), Highres Multitrack Field recording and other audio productions where compactness is important.

There are new Micro PCs announced later this year with more powerful processors and USB 3.0 interfaces at the size of an USB-stick, dreams come true

PS.: Now there is only missing a Octamic XTC with a form factor of QuadMic or even smaller