The question is this: Is it more important for your guitar cabinet to shake your pants legs from the backline, or is it more important for your band to have a kick-ass mix and sound great through the mains? Are you an amateur or a pro? I hate to sound harsh, but that's the difference. I have run sound for other bands while playing in my own band, and it has taught me a lot about getting my best sound at gigs.
The biggest challenge in live sound with a rock band is in small venues. With a big room or (of course) a stadium show, your stage volume can be crazy loud and the sound guy can work with it. I played a covered amphitheater with an Engl Powerball II on 7 through a 4x12 and the soundguy didn't blink. But let's face it - most of us (me included) aren't playing stadiums or even bigger rooms most of the time. The majority of our shows are in small to mid sized rooms, and you simply cannot get a great live mix in a small room cranking a 20/50/100w tube amp through a cabinet.
Turning the cab around will lower your stage volume, but you won't like the sound much. A plexi shield also helps reduce stage volume, but it often reflects too much sound back toward the drummer and your tone onstage can get funky. Sidewash can sound great, but then you risk overpowering the singer/bass player/other guitarist with your sound.
Guitarists (and drummers) find it hard hearing the facts of life for live sound in a small room, but here it is: Everyone needs to go direct. Everyone.
That includes your drummer (because most drummers don't know what dynamics are). Electronic drums sound amazing now. I can't tell you how many small club gigs I have heard where the unmiked drummer was louder than the rest of the band. Cymbal crashes drowning out everyone else. Going direct, your onstage sound will be pretty good, everyone can get mixed well in the monitors, and if you want to hear yourself more than the sound guy can/will put in your monitor, bring your own wedge and run a second DI signal.
Anyone playing a small room should seriously find a DI system they can live with, be it Kemper, Axe, Digitech RP series, Torpedo, etc. We all complain that we really want the sound of our beloved tube amps when we play live, but it's time to face facts: your great tube amp tone is never, I repeat NEVER translated accurately via the PA in a small room. You can adjust the mic placement all you want, and the sound guy will still EQ you to sound like shit. But with a direct out, most sound guys don't feel the automatic need to EQ you to hell. Just tell 'em you've got it EQ'd internally and they will usually leave your signal alone.
You'll sound better live tweaking decent patches in an RP1000 and giving the sound guy a consistent line-level signal he can work with than you will trying to tame a beast of a tube amp for a small venue.