I am partial to the brother, I have had a couple, they have several different models that are the combined. Since you already have a brother you are familiar with the operating system as well, most are similar but there are some differences. You won't have to translate any patterns you have either to fit the new machine.
The ones that just embroider and not sew as well are more stable in my opinion, and less expensive, the dual machines tend to be more expensive, so if you have a good sewing machine may I recommend that you by a dedicated embroidery machine, that way you can sew and embroider at the same time.