I have one of the HRTs and use it daily, although I am getting deaf, so not sure if it's any good. I'm certainly happy with it.
I also had its predecessor, although it didn't have standard TRS or XLR outputs, so I needed to get special cables made.
I also have one of the Steinberg UR22MkII, with ADC and DAC made by Yamaha, I believe, but I use that for recording. The big difference with the MkII is the sample rate, I believe, so before you see the Mk1 for $75 and cheaper used and go out and buy one, you may want to look at its sample rate and make sure it is adequate for your needs.