I prefer Downtown Camera to Henry's simply because the staff is more attentive. I rarely every buy camera equipment retail (bodies and lenses), so I am only basing this review on accessories and my knowledge of their operations. Here's a breakdown:
1. They have some very good weekly specials. A good sale pops up once in awhile, especially for a full beginner SLR kit.
2. I purchased a Manfrotto tripod kit here for $150. It was on the lower end of the tripod spectrum, but the same kit was retailing for $230 USD on Amazon. I consider this to be a great deal, especially for Canada.
3. Staff is great and a lot more laid back than its neighbour. They're also very knowledgeable without being arrogant about it.
4. Excellent selection of goods from all manufacturers. It is a lot bigger on the inside than it looks from outside.
5. Regularly prices are moderate (perhaps overall very slightly cheaper than Henry's).
6. Store layout is less confusing and easier to find what you need.