The Summit Audio TLA-100A works in a program dependent manner, meaning it does a lot of the thinking for you. It's tremendously easy to use and basically impossible to make it sound bad. It will however give you some soft and warm distortion if you drive it really hard. For ease of use, Softubes TLA-100A plug-in has a Saturation knob that the original unit lacks. This lets you blend in just the right amount of distortion to your signal.