As we all know (I hope) overdrive designs can have very different frequency response curves; many are tube screamer variants that have a midrange hump, but there are many other different types. I've been through a boatload of the damn things, and of course have also been a guitar>cable>amp guy at times. I prefer an overdriven tube amp to a pedal for most things, but there are times I need an overdrive. I recently went back to the OCD because it's fairly neutral, that is, it works with Marshall, Blackface, and Tweed style amps. At one time I would put an overdrive up with a given amp, and think, "this overdrive sucks." Then I learned that it's really important to get the right one for a given type of amp. Just thought it might be an interesting topic for discussion.