What are you trying to achieve? Keeping the basic tone of the Renegade, and just drive it harder, or get a different tone altogether? When I had my M4 with the SL module, I really liked the BB for driving the SL harder, and getting it into SL2-ish territory, but I didn't really think the BB changed the overall tone of the module drastically - i.e. it still had a very Marshally flavor.
I have been looking into some pedals for my Renegade too, but I am looking to add completely different flavors of tone. I am curious about pedals like the Tone Freak Severe - the clips sound very Rectifier-ish, or the AMT R1, and the Vox Cooltron
Over the Top Boost - which is supposedly a
AC30 Top Boost-like circuit in a pedal. Basically curious about running pedals like that into the clean channel of the Renegade to effectively add a third or fourth "channel", as opposed to a overdriven version of the existing channels.....at least until the E2 is ready.
When I do want an overdriven version of the existing channels, I've been using
a Fulltone Fat Boost v3. I'm not sure what the differences are between the Fat Boost and the OCD, but I'm really like the FB3 a lot. I pretty much have it on all the time - it really helps make up for the losses I get when running through my other pedals (even the "true bypass" ones). And it has a nice drive circuit when I want it to not be so transparent.