I have the Janome 6500P and love it. Have not had any problems at all with it. I piece, quilt, stitch in ditch and freemotion with it.
Decide what your pre-requisites are and look for something that has them and try it out.
Mine were automatic needle threader (poor eyesight!), needle up/down, longer bed than average, knee-lift.
I don't have embroidery capability which isn't an issue with me.