Do a Google search, for "Baby Lock Melody reviews." You should be able to find some opinions, from other folks who own one.
Also look into the availability and cost of accessories, for each. I have a Janome 7700 and one thing I really love about it, is the convenience and ease of buying bobbins. It takes the same bobbin as my Brother, so I don't have to have separate bobbins for each. The bobbins are available at WalMart, so couldn't be easier to find!