Well, I have recently started stacking a Boss OD-3 into a Boss DS-1. Sounds great. I have been using the OD-3 as a heavier crunch than the amp and the DS-1 as a lead sound with the volume up a tad and the drive at a moderate level. They blend together to make a more complex third sound, which is cool. Someone suggested running the higher gain first so I tried that and it does retain the higher gain but without the squeels, artifacts and noise. It was more controlled with higher gain first but I am not convinced, I like the thing where it almost going out of control with the DS-1 after the OD-3 rather than the more polite alternative... What is everyone doing ? and Why?