I your'e plugging guitar or analogue effects in, please don't. Do yourself a favor, and try it b4 buying you'll realise that any reasonable guitar amp will sound better. The only time u plug a guitar into a k/b amp will be when you're using an amp modeller or multieffects with modelling tech.
Granted if you're talking about accoustic guitar maybe still acceptable (barely), but no way for electric. Anyway for accoustic can go straight to P.A. I assume that you're buying for your church since u mentioned the word congregation.
Since u have to ask, i assume that you're not the church guitarist, but looking to save money by buying an amp that can so called do everything. Trust me it won't work. Your guitarist will put u on his hate list!!! Have u consulted your guitarists on this issue? Don't even consider buying an amp and have 2 people share it as well. Why cos guitarists (any musician) when playing would need to hear himself/herself. Having 2 people share would make it more difficult to do that and adjust the individual tone. I would be very angry if the one doing the purchasing did that to me.
Actually can try the behringer 30w at $250 each. Try to get them to up the budget by $100. If not, the pathfinder 15w should be gd enough. Just mike it up. Anyway as far as i know in church we try to keep the stage vol down.
I hope this helps and God bless your church.