I sometimes use a UA Solo 610, which I think is similar sounding. We first tried it as a direct box on bass, which is a common application, and it sounded good but a bit soft. A Countryman Type 85 turned out to be the sound we wanted, full but clear and solid. The 610 did turn out to be really nice as a direct for a pedal steel. It softened the slightly hard edge to the instrument's sound. I've also plugged in a variety of mics on a variety of sources and the general trend was toward big and warm with a slightly softened tone.

I have 2 of the mkI's they are the same but the MKI's are a little more limited. The compressor in this is crazy good and worth the price alone. Sometimes you can get a bit too much sibilance with it but nothing that isn't easily dealt with.