I had a Brother 8500D and never had any problems with it. I upgraded to a Brother Innovis 4000D and have not have any problems with it either, it's about 4 years old now.
Both are combination sewing/embroidery machines but I have to admit, I never sewed on the 8500 and will probably never sew on the 4000 either for 2 reasons. I have the 4000 on top of a dresser so I have eye level access to it, it would be too difficult to move it to a table to sew. And I do a lot of embroidery and I have a really good regular sewing machine so usually I'm sewing and embroidering at the same time.