I’m in Montreal, but my knowledge of the schools here is limited as I went to Arizona State for Uni.
Kevin: You mention working in a civil engineering firm. Are you doing CAD work now? My impression is that cegep are a little more technical oriented, therefore if you already have great CAD skills, you might find cegep redundant.
From the UdeM grads that I’ve met and shows that I’ve seen, it does seem more focused on theory and concept. That would definitely challenge you.
UQAM does seem unfocused, although some of their grads have gone on to do great things. If you have a good idea of where you want to be after graduating, it might not be a problem.
For Laval, it’s like Louis said, who knows. I hadn’t even heard they had a program 
I hope you keep us posted once you have made your decision. Best of luck!