I have an A1. Drive all the machines - this is like buying a car. You don't want to end up with a Yugo when you may have a budget for a Lincoln or a Ferrari! YOU are the one who gets to determine which machine is which car, and where your budget lies.
One feature that I would not do without is the ergo lift. LA quilting is very physical. Sometimes, just an inch up or down can make a world of difference on your back. I use different heights for the front of the machine (standing), front of the machine (sitting) and the back of the machine (doing pantos). Also make sure your handles can be adjusted. Again, sometimes just a little tweak can be all the difference you need for ok control and ultimate control.