Here are my latency figures from Ableton. I have a pretty high end PC, and it is stable at a buffer size of 256. Sometimes I will have to switch to 512 towards the end of my projects. I have the Asus EX3 thunderbolt card. Unfortunately I have many issues with the stability of this interface, but trying to get it fixed through support. This interface would be great if I didn't have to struggle to get it to work properly without restarting/reseting all the time.
(Buffer size 32) - overall latency: 2.72ms, input latency: .91ms, output latency: 1.81ms
(Buffer size 64) - overall latency: 3.45ms, input latency: 1.63ms, output latency: 1.81ms
(Buffer size 128) - overall latency: 6.35ms, input latency: 3.08ms, output latency: 3.27ms
(Buffer size 256) - overall latency: 12.2 ms, input latency: 5.99ms, output latency: 6.17ms
(Buffer size 512)- overall latency: 23.8ms, input latency: 11.8ms, output latency: 12ms
(Buffer size 1024)- overall latency: 47ms, input latency: 23.4ms, output latency: 23.6ms
(Buffer size 2048)- overall latency: 93.4ms, input latency: 46.6ms, output latency: 46.8ms