I have a Viking Designer SE LE and love so much of what it can do. There are things that drive me bananas and resulted in getting ansecond machine, so a word of encouragement to run that sucker through its paces at the store. Drag in the lightest fabric you ever think you might use and do some fancy work on it, take in your biggest quilt project and shove it in there to see if you have ample maneuvering room, run the embroidery unit too. Bring your fabrics, and spend a few hours ripping along. Make notes about questions that appear to be no-buy issues and have the sales person answer them. Sew like you do in your machine now and see how you like it. Its the little things that you dont even realize when someone else is doing a demo that will not be like how you sew. like how far into the fabric do you have to be at the start to avoid sucking it into the bobbin housing, or does it hate to chain stitch.
One of my local stores insists you do this before buying as they believe a several thousand dollar investment that should last many years requires that amount of due diligence. The other store insists on doing only a specific demo and letting you watch.