What I did (and usually recommend to anyone who asks) is make up a spreadsheet with your 'wants' and 'needs'. Take a look online at the various machines out there and see what features they have. Add that info to your spreadsheet. Lastly I look at price. (I don't find you can get accurate pricing online for sewing machines anyhow). With your budget you will have many choices open to you. After that, go to your local dealers with, as others have said, practice pieces of things you typically make or even anticipate making. Check them all out then talk price. Most dealers will haggle on pricing or at least heavily discount the MSRP.
You may want to even consider an older, reconditioned machine at one of the dealers. You may get a bigger bang for your buck. FWIW, I have a Viking Platinum and love it. I don't do machine quilting so it more than covers my needs. Actually, I do MQ charity quilts that require it but otherwise no.