Regarding availability of consumer goods, you guys in Canada are so getting ripped. I've no idea why this needs to be so.
As to the RW-12d, yes, it's considered to be the Top Dog of it's price point. It's nearest peer is a BIC, PL200. Is that something one can easily locate in Canada?
As to encouraging one to purchase a BIC, Venturi, V1020, in all seriousness, I would encourage them to try and find better. Yes, the output makes a difference. If cost is a limiting factor, then I would encourage something that's used with some sort of a warranty regarding it not being DOA. Unfortunately, one takes their chances with used.
A suggestion, checkout comments in the budget subwoofer threads and see if there's anything mentioned, available in Canada, which peaks your attention.
As to your thread's title, very much so it makes a difference. In the case of subwoofers, bigger is better and the more subwoofers one has in their system, the merrier. My recommendation is buy one 12" subwoofer with your mind's eye on adding a second and/or third one down the road as you're able. The difference is wonderful.
Once you have a system that reproduces wonderful, you'll understand.