What is your stage volume like? How big are your stages?
Do you think that getting more monitors is more important than good quality monitors? Would you suggest getting 4 lower end speakers over 2 really nice ones?
I could get a midrange 18" sub and 12" tops for the same cost as the high end PRX 3 way speaker. Do you think a sub is that much better than the 15 in the three way JBL?
Our stage volume is OK, under control, but our drummer can make a bit of noise.
Stage size varies wildly. From being jammed in a corner inside, to the back of a semi-trailer outside at a car show.
If your stages are small and not many people sing, you might get away with only 2 monitors.
@xrist04 alluded to it, but what is the budget for this? And what does that need to include (stands, cables, mixer, etc.)
Me personally, I got the monitors I have now by starting with 2, then a 3rd, then a pair of DSR's to make 5 (or to use as fills/spares/different location, etc.). Putting the money I made from gigs into building my PA.
My first monitors were JBL EON's and they were CRAP! (IMO). Prone to feedback, sounded horrible at volume, very muddy like a blanket over them. So from personal experience, don't go cheap. The Alto's seem to have an OK name for a budget monitor, but I've not got any personal experience.
Maybe your drummer who runs direct can supply their own monitor (even headphones) to save you some upfront costs?
I had the PRX615's for a while as my FOH (with a single 618xlf sub) which did work quite good.
Without the sub, I wouldn't have wanted to run both bass and kick through the tops, they just didn't have the impact I was after (I want to feel the bass and kick in my chest)
I'm expecting that impact you will also miss with the 835's, although you should have a nicer midrange and smoother around the crossover areas compared with my 615's.
One last thing to consider, although it might not apply, I do a heap of Acoustic shows as well. Single 12" on a stand for FOH and another as monitor. I would hate to carry a 3 way box into a small cafe that only holds 40-50 people. DXR10's would be fantastic at this though so you might be OK depending on your monitor choice.
I've put below some photos from earlier this year if you're interested at all (different bands).
The first one we played a 30th to about 100 people. Bass was direct, only kick and snare got mic'd - it sounded great (full, loud, clear) Bass player was happy to have his own monitor and mix. He would have been fighting with the singer or me if he was sharing a monitor/mix.
The second we played a fundraiser to 750 people. Everything was running through FOH, but we still had a bass amp on stage.
3 foldback up front, drummer on IEM. Bass player didn't have his own monitor, but had his amp to be able to hear himself.
IMO there still wasn't enough low end for the big room, but nobody else seemed to mind to much. It was more a cocktail function than a rock show anyway.