I got a used Janome 350E and am very pleased with it. It is an embroidery only machine. I also have a Janome Horizon.
I like my 350E because 1. I can sew while embroidering...both machines going at once, so, in a sense, I can do double duty at once.
but secondly, since it is a Janome, and I also have a Janome Horizon, it uses the same size bobbins!!! That is a HUGE plus. I love it. I can fill the bobbins on the Horizon and not have to stop embroidering to fill the bobbin with white thread.
I've never had a combo, so I can't comment on one.