Huge reliability issues with that pedal(zwod). I bought a used one despite the reliability issues i read about and sure enough, it went. Usually it's just a switch related problem, but thats a dealbreaker if your a gigging guy and need reliabilty. With rectifiers in general, and i owned a roadster combo for a few months, any old tubescreamer or one the 10,000 variants of a ts circuit works awesome. Some people dig ocd's for boosts, i don't. I love the ocd into a clean fender twin or any clean amp for od/dist, but not with mesas. A tubescreamer attenuates the lowend and makes it tighter, adds a nice amount of compression and actually makes the gain a lot more articulate IMO. Anything from an Ibanez ts9 to high-priced boutique TS clones all work awesome for mesas gain channels. If your not sure, grab a used badmonkey for $20 or a boss SD1 for about the same money and try them. You can spend a lot more, but i find those pedals work just as well as my more boutique tubescreamers.