The one that meets all your needs and you are happy and comfortable with, which can do the job you want it to do, is the one.
Asking a friend to go with you, is a good idea. Just remember, a good friend will speak up if it is not the right one. If you ask for their advise, it is important to remind yourself, they will give it. Chances are they may be more honest, with their response. So be prepared for an unbaised response. A good friend will have your best interests at heart.
This is the one that won hands down. Janome 625 E. This one was tested at The Sewing Cafe.