Don't have a 104 key to compare with, but I didn't think they would feel different, jus curious as to why. I chose the 103 key for a larger space bar and a more uniform look. Didn't see a need for two windows keys.
I like the look of it too. It looks too good to be true. You put a 101 next to the 103, and you can see that this is what they should have done to begin with. If you are a purist, you can say the 103
IS the replacement keyboard to get. Is it necessary to have the extra keys? Not really. I like having them, however.
I like the longer spacebar too. Too many times on other boards I hit the comma key or the period key and toggle out of what I am typing. So YES, I do notice a significant difference.
It's perfect to me. Isn't that what it's all about?
Edit: Good thing I don't accidentally hit Alt-F4 too often hahaha!
Edit #2: Oops.