I agree with others, the best time to buy is at a show or sewing event. Here there are Floriani events through out the yr and they sell Brother, then Viking has events at our LQS and then in Feb there is the Hampton Roads Quilt show and sometimes a few others in there. You get the best deals. I bought both of my high end machines from our Viking dealer, they were used but came with a warranty, when I traded in the first one, I got almost the whole amount I spent back on the 2nd one. The 2nd one came from Vikings Yearly event with dealers, it was set up to use if a dealer needed. I got all the bells and whistles, the luggage and full warranty and spent several thousands less than normal.
You should go try out different machines, write down the features you like and want, needle up/down, knee lift, auto thread cutter etc and then compare and try out any machine you think you might want or try them all out because you never know you might find one you hadn't considered a great choice. You can't beat good customer service. There is one high end machine that lots of people love that I wouldn't even consider because of the store, they have lousy customer service on daily things so I wouldn't want to deal with them on something major like this. Make sure to find out if you have a problem will someone help you trouble shoot, do they have to send the machine off for repairs, etc. I'm sure you'll get lots of advice and pay attention to it all but make sure you feel good about what you are getting. Most of the high end machine companies offer free financing so that can make it easier and more affordable. Good luck and Merry Christmas and Happy Holidays to you as well.