I see! I used it on my nano for years. I flipped it sideways and put my compressor underneath. Together, they used the same amount of space as a Shiftline/Sansamp preamp. I sold my Zvex to buy another drive pedal and boy, do I regret that. I used the Zvex as a set-and-forget OD and for that purpose it was lovely.
My second suggestion would be the Mad Professor Amber Drive (for bass, which is available on their website). It sounds huge and is easy to dial in.
The WM Smalls Pork & Pickle would be a great compromise as well since it serves as a drive and/or fuzz.