Well basically im seriously considering getting an OCd for my BD and need to pre order from UsA. But i know it can get those clean sorta screamy bluesy tones, but i am wondering what it would sound like in "harmony" with my DSL 401s distortion. Im looking for a tight sorta sound, the nearest thing i can think of is a mesa kinda wall of noise, kinda thing, but also very tight like on the songs "Symtoms of the universe" by "Black Sabbath" and "Into a void" by them aswell. Like im happy with the DSLs distortion just looking to tighten it up a little, for those metal tones, aswell as using it on clean channel for screaming blues, such as hendrix and clapton. Furthermore would this work as a volume boost, i assume it does?

Sound samples from you would be great!
Yea, I think an ocd should work. I've never tried it on a DSL but at least through my orange it can help shape the cranked tone nicely. It still sounds basically the same but it works good for controlling the sound and tightening it up. If you like the way your amp sounds I'd say it will probably work fine.
A Tubescreamer is usually used to tighten up already distorted amps. I don't know if an OCD is good for this, but you should consider a Maxon Tubescreamer version if you want to tighten up your tone.
12 fret fury