I've had the Keeley BD-2 Phat mod now for about two years. It takes a great pedal and makes it killer. Ever since it was modded, it has never left my pedalboard. Keeley is a top notch company and easy to deal with. They mod and ship back very fast.
I also had an old Japanese Boss DS-1 with the Ultra Mod. It took, IMO, a terrible sounding, high endy, buzzy, no balls pedal and made it useable. However, it still wasn't that great. If I understand correctly, Vai uses/used his on top of his already overdriven Legacy. When I used the DS-1 in from of my old Marshall's dirty channel it was ok and gave it a more complex sound. But engaged alone in front of a clean channel? I've heard some Behringers that I like better! I ended up replacing it with an AMT California Sound and later an AMT British Sound and I don't think the Keeley DS-1 Ultra can touch either one.
My two cents...
~ Jason
