There is nothing bad switching to Thunderbolt. From what I read in the forum you might have challenges to get it working depending on the BIOS, TB card (if you need a separate) and adapter cable being chosen.

From driver / performance perspective, the thunderbolt driver has only a little lower RTL.
See the overview about RTLs of different RME solutions in my blog article about UFX+:
https://www.tonstudio-forum.de/attachme … es-v2-jpg/

I have no thunderbolt capable PC, but as thunderbolt is “external PCIe”: when I compared USB3 vs. PCIe (UFX+ USB3 vs. RayDAT PCIe) there I couldn't see any significant difference.

Theoretically, PCIe/thunderbolt should have less driver overhead and maybe consumes a little less CPU. But it is difficult to measure without special monitoring because CPU load is instantly changing. So, I concentrated more on something like an “application stress tests”, by creating a large Cubase project creating a high load on the machine.

400 audio tracks running 2 VSTs in each channel at 44.1 and 96 kHz. Then I concentrated my observation on whether I get audio dropouts during playback at the lowest possible ASIO buffer size at 44.1 and 96 kHz or not. For me, that was fully sufficient to validate, that I get excellent performance through USB3.

There was no significant / visible performance difference, also no audio drops in both cases.
See my blog article here: https://www.tonstudio-forum.de/blog/Ent … cks-de-en/

There is a little functional difference between MADIface USB and Thunderbolt driver. Only the thunderbolt driver allows for pitch. If you want to use pitch as well for MADI connected devices, then you have to switch to MADI 56 channel mode, if I understood this correctly from manual.

I, personally, see advantages for me in using USB3 because of the higher maximum cable length which is 3 m compared to 2 m with thunderbolt. You can also use USB2 with 5 m with the restrictions mentioned in this thread, see
https://forum.rme-audio.de/viewtopic.ph … 37#p193737

As mentioned in this thread, there are optical converter solutions available from corning.
I just ordered such a corning solution for USB3 for 10 m (they also offer longer optical extensions up to 50 m).
It is powered by USB3, so no other power supply required.
This allows me more flexibility to move my recording rack a little further away from the desk for cabling, cleaning etc.

These Corning cables might also be a little pricier for Thunderbolt compared to USB3. Usually, everything for Thunderbolt (cables, adapters, mainboards, etc.) is more expensive.