When it comes to Bernina and Janome you will have die hard fans on both sides... you will really need to go test drive them both and see what you think.
Having said that - I have a Janome 4900qc and love it. It's a fantastic machine. As much as I might have considered a Bernina, they are a little bit pricier which is a turn off to me.
No matter what you decide on this, you will be happy either way. :)