Figure out what features you really NEED, and which ones you really LIKE. Don't rule out a good used machine as you might be able to get more of those need/like features than you would have if you limited yourself to a new machine.
I love both my machines for different reasons.
Steady Freddy the Viking is tride and true and never misses a step. He's somewhat limited though in ability especially with regard to FMQ and I've had a problem with my local dealers keeping or even getting stock of different feet.
Fancy Nancy the Janome is lovely but she's a finicky *&%^$!! She demands only the best thread in the right weight and will get an upset stomach if I don't use the same thread top and bottom. She's got some really cool FMQ features though that my Viking doesn't have.