I want to necro this to let anyone know that’s still looking…
Tech 21’s Deuce Deluxe is a powered cabinet for guitar and bass. The stock speaker is just fine. Probably easily on par with the Powercab. I personally put in a Celestion F12-X200 to try that out, and it leaned the setup more toward excellent guitar cab vibe, but still handled bass. If you’re genuinely doing both seriously I’d keep the Deuce Deluxe’s stock speaker in.
I saw really no drawbacks. It’s a powered bass cab that can do guitar just fine.