I like your photos very much.
One thing I notice about them is how comfortable you are with the 4:3 aspect ratio. The 40D would show 3:2 in the finder, and you'd have to crop after the fact. Many people find this hard, annoying, distracting or outright impossible. There is the very real possibility that using a Canon DSLR would cripple your photography.
3:2 was never popular for landscape before digital came along. At least some of the Nikon DSLRs have or had masks in the frame to make them shoot 5:4.
Everyone is different. There is a whole school of landscape photographers that shoot 3:1 (the "617" format). That's the way they see.
I think your neighbour is right - don't try to fix what isn't broken.