That's the rig I've been rocking for a while now and I've found it to be super flexible. You'll probably find that both cabs will be more than enough for just about any but the absolute loudest situations.
I only need one cab for my funk band rehearsals. It's more than I need to keep up with two vocalists, guitar, keys, drummer and 5-6 horns. I do bring both cabs to gigs, but more for looks. One might be enough, but it's nice to have the extra oomph if needed.
For gigs with my gospel band, I automatically bring both cabs because describing that band with "stupid loud" wouldn't be a stretch in the slightest. Lead vocalist, TEN backing vocalists, two keyboards, a sequencer, myself... and a drummer who only has LOUD and LOUDER. (One of the keyboardists and I continue to try and convince the band leader that louder doesn't always mean better... But he seems unwilling to entertain the idea.)
My PF rig sounds awesome with pedals too. I use mainly overdrive, octave and envelope filter, but I'll throw in the occasional chorus too. It sounds awesome with everything and I don't bother with the effects loop either... Board goes straight into the front input.
Edit: I'll also add... Don't be shy with the volume knob. The PF500 seems to really hit it's stride around 1:00-2:00 on the Master.
5sg.
Awesome! I'm really looking forward to this, Thanks 5sg!