Thunderbolt audio interfaces with Windows support ...do they exist?

It seems not yet. I was just asking about this on Facebook as I was really hoping to get a UAD Apollo but it's not yet supported. They do have a new Apollo Twin USB for Windows so I'll likely pick that up soon.

Most likely native support for Thunderbolt 3 devices in Windows 10 will arrive fairly soon. Presumably this will run new or existing Thunderbolt 3 devices if any, but support for versions 1 and 2 is not guaranteed. The thunderbolt 3 connector does not fit earlier sockets, but some connections can be made with adapters. Most of the existing computers and devices use earlier versions. It is pretty difficult to imagine how you would get any meaningful benefit in an audio interface using this connection over firewire, or USB for that matter. That said, in a few years, you will probably find devices that will keep your coffee warm if plugged into a Thunderbolt 3 connector. So if you want to future-proof your DAW (and keep your coffee warm without the kludgy USB cord) be sure to get a Thunderbolt 3 machine. Thunderbolt 2 is soooooo last year.
 
http://www.synthtopia.com/content/2016/01/29/microsoft-announces-plans-for-thunderbolt-support-in-windows-10/
 
http://www.zdnet.com/article/thunderbolt-3-beating-a-dead-horse/
 

The advantage to Thunderbolt (if you're using Thunderbolt 3) is that we now have "PCIe via Thunderbolt" drivers.
You have to be running a Z170x motherboard (with USB-C connection) and Windows 10.
Performance will be similar to using a PCIe card.  
 
Regarding USB not being up-to-par for audio:
The RME Fireface UFX is a excellent performer when connected via USB2.

• 30 channels of I/O
• Can operate glitch-free at a 48-sample ASIO buffer size (as long as your machine can sustain the load)
• Round-trip latency at 48-sample ASIO buffer size/44.1k is 4.3ms

 
Running "PCIe via Thunderbolt" (or a PCIe card), you can take the ASIO buffer size down to 32 or even 16-samples.
That results in extremely low round-trip latency (in the 2ms range).  
This is the main advantage to Thunderbolt (or using PCIe card).
 
PCIe via Thunderbolt (or PCIe) does have many times the bandwith of USB2.
BUT... if your audio interface is nowhere close to saturating the USB2 bus, simply increasing bandwidth won't increase performance.
Liken the situation to your automobile.  Your car may have a top speed of 120mph.
Doesn't matter if you drive on a two lane highway or an eight lane freeway, your top speed is 120mph.

kitekrazy1
 I often wondered why on consumer end audio interfaces companies like M-Audio and Echo never bothered with  pcie. It seems it went from PCI to USB2.  Even Creative made PCIe cards.

USB peripherals are easy for a novice to install (no opening of the case)
 

this was linked in a sonar thread under computers
 
https://www.gearslutz.com...port-windows-10-a.html