The interface is okay, but I can't hear much of a difference with the 4K button depressed. It's SUPPOSED to emulate the sound of the pres on a SSL 4000. I hear a bit of air and distortion...nothing else that seems usable. I think the pres on an SSL 400 sounded MUCHO better. Free bundles of offered software are hard to get , if at all possible. Most require a download of a specific plugin manager, that takes up space, but then you have to fight with CS to find out where to put in the code....With Amplitude, I gave up. Impossible. and with most, like SSL itself, don't expect a quick answer or a solution. Extremely poor.