I can say that the B&W 683 for front speakers will be superb, I have auditioned them and they sound just fantastic. I would go with the B&W's even if it stretches your budget it will be a life long investment and well worth it in my opinion.
You could save a few bucks by going with an
SVS PB12-NSD/2 on clearence right now for only $799 and I guarantee that it will out preform the B&W.