Here's another thread from this morning that may give you some Food for Thought!
http://www.quiltingboard.com/t-152308-1.htm#4185108
An additional thought ... choose not only the machine, but the dealer where you know you will/can get the service you may need.
I heard a horror story the other day ... I met a professional seamstress at the store where I purchased my 6600. This lady who "loves" Bernina had problems with her machine. Sent it to her local dealer, and after 3 yrs he had not fixed it, claiming it needed a new motor and he could not get one. She got on the internet, and found a motor via the store I deal with. They shipped it to her. And the original guy, couldn't fix it.
She put all in her car, and came to visit her cousin in the same town where she'd ordered the motor (24 hour drive!). Guess what, the problem was NOT the motor, and they had her machine fixed in 20 minutes!!!
Guess what? she now deals exclusively with this store. While inconvenient, they can ship her what she needs overnight and most times she can do it herself, with the shop's service mechanic for advice if needed. When she does come this way, she brings machines for servicing and they rush them thru while she's in the area.
Service. Service. Service!