My little tiny toy-sized Janome works pretty well. I decided to use the machine for the replacement bodice, and instead of the sewing taking up the entire evening by hand, it took about an hour with the little zippity machine. Mind, it shouldn't have taken that long, but I was having major issues--bobbin seizing, thread breaking, tangles, GRARR!--then I paused, really looked, and realized I'd left the bobbin-winder on. *facepalm* I had the machine on an Ikea lap desk, with the foot pedal under my crossed knee, and aside from motor noise, it was all easy, convenient, and not too terribly infuriating. Anyone interested in getting one should know that it will not go through more than four layers of medium weight fabric, and even then, I think the machine would have preferred gauze or light silk. Or kleenex.
And yes, I have Amazon Associates links here, and little ads to the left. All the same, I bought it at Overstock.