My Juki 2010 sort of thumps along with the walking foot in a solid and reassuring way. On a heavy table, it doesn't vibrate at all. The Viking purrs gently by comparison, but now that I have both, it seems a bit flimsy and finicky. I love the Juki. It might be useful to sew on all of them for a comparison. Wouldn't dealers likely feature all 3? I know it doesn't make sense, but when I bought the Juki, I didn't bother to try the Jane because of the Juki looked more like a serious machine to me. I couldn't get past the little skirt logo. (Which maybe comes off, but I was so taken with the Juki, I didn't ask).
hugs,
Charlotte