I just spent a good deal of time investigating machines. I had ordered a Singer Quantum L-500 from HSN because it had ALL the features that were important to me but it was too rough for me. (I'm used to a smooth Pfaff ride) I sent her back.
Then I went back to the dealers and test drove all the other models. Turns out I fell in love with the Babylock Espire - She was on sale and came home with me. What did it for me? The one-touch needle threader, great lighting, smooth operation, and the bloody thing sews sideways and angleways. Not sure if I will ever need that but it's like a car that parks itself. HOW COOL!
One place I got a lot of info was on patternreview.com They have a machine review section and lots of members write reviews for lots of different models.