I think things are a little different from prior comment. USB is not the best generally. Yes drivers are what matters most but in practice we find USB is not the best implementation. I follow and study audio interface latency...by reading the work of a few people. There is one guy doing really cool testing research and he has a big thread somewhere with charts etc..it seems legit and I am careful about calling something legit.
https://www.gearslutz.com/board/music-computers/618474-audio-interface-low-latency-performance-data-base.html Long thread, bulk of charts is in the middle somewhere. He also does Dawbench stuff that is related work and I follow that too. http://www.scanproaudio.info/tag/dawbench/ His work is really valuable will hopefully be disruptive to the soundcard makers industry..so they care more about drivers. It matters much more than you think, because surprisingly it turns out to not just be about perceived latency. Lower latency sound interfaces result in better resource performance from a given computer...meaning you literally get more DAW performance and plug in counts etc with lower latency. They are correlated. This is surprising, but if you want the most DAW performance from you computer, you want to lowest latency. So it literally is the case that the lower latency soundcard is in effect giving you a much faster computer ! Yes RME are the best but also quite expensive can be 2x the cost of your computer. ! USB in some ways may look to be comparable in 'speed', but it can never be a 'quick' as PCI. There is something important about thunderbolt because it is actually an 'external PCIe' connect. The Presonous Quantum has made a name for itself among those close to this issue. That is likely to be the one I will try. Yes many of us are quite pissed that TB implementation is so piss poor slow to come on desktop motherboards, while it can be found quite a bit more commonly on laptops (but laptops can still be a bit slower and always cost more and other limitations (and benefits). Yes we've been long aware that the ONLY current mainstream MB with TB built in the the ITX Asrock. And the TB being built in is the ONLY type you want. The add-in cards with wires that connect to headers on the MB are known CRAP!. I don't care how much luck etc you might here, all too often it is YMMV, instead of it actually works reliably and hassle-free. If you can even find a card, that must be the same brand as the MB, and the MB must be TB ready-with the header on it. I am so feed up I am considering caving and getting the ITX, though I really want mATX or ATX. and the TB on the Asock is only 20gbs ! (half speed) This may not matter for audio/midi though, idk, I will have to research that before doing this. Also the ITX only has 2 ram slots and only one m.2. I can live with only one PCI slot but the other two things are a gripe. However given it's the ONLY one, I may do it. Also you could build X299 (intel) but it costs way more, and it actually not quite a efficient etc as coffee lake (which is really good chip actually). It's not clear if Intel willl make refresh cpus for X299. The Gigabyte Designaire EX is a good choice for built in TB etc if you want to built X299. In a best case the 9900k would already exist and z390 MBs would actually have built in TB. Don't count on the later ! grrr. Though yes you can do even better if you go above 8 cores on X299.