First, I know nothing about longarms, just what I've read from quilters on sites like this. However, If I were considering spending $10,000.+ for one, my homework would begin with using several and talking with others who live close to you about their service.
I'm in a large metropolitan area, so there are several quilts shops that offer rentals by the hour. You have to take a class in that machine (usually $75.00) before you can rent time. Some shops sell those machines and some just offer the rental as a source of revenue. You are not too far away from Tampa and Orlando to take those kinds of classes. It not only would give you a chance to use the machine and see how you like it, but to know what to expect when your machine is working correctly.
The other thing I would want to know, is how responsive is the dealer in your area? How long have they been in the long arm business? How many technicians do they have? Can you visit with some of their current clients (both new and old) in your area? How far away is the dealer?
Then, how responsive is the manufacturer? What if your local dealer goes out of business. What if they don't have a local dealer? If they don't have a local dealer, what do you do when you have a serious problem? Do they send a technician? Who actually sets up the machine?
It seems the people who have the most problems are the ones who can't get help when they are initially learning (or setting up) the machine and have problems. There are long arm groups on Facebook (some are specific to brands) and on yahoo groups. I'd join those groups and ask questions.
Be aware that the people demonstrating at the shows are good sales people. If they weren't good at selling, the manufacturer/dealer would not have them there. Participating in trade shows is expensive, so persuasive sales people are a must. Don't be persuaded to buy something you are not sure about. Since you set March as your decision date, beware of making a decision just because it's March.
For me, $10,000 is a lot of money. I'd want to make the best decision possible.
This is just my uninformed opinion. Take it for what it's worth.
bkay