I got mine because I just couldn't FMQ on my regular machine because of the problems it caused with my neck and back. I have a couple of LA friends and I tried out their machines, I went to shows that featured LA vendors and tried their machines and I joined online groups that discussed LA quilting and asked questions of those who had machines. I talked to the Nolting people in Iowa a lot and just decided that this is the machine for me.
I agree with you, it is a big decision because of the cost, but I'm glad I did it. Talking about the cost of LAing, be aware that the cost you incur is not just machine cost. If you go into business with your machine you will have licensing costs and supply costs and training costs to consider.
After all is said and done, I'm really glad I made the decision to get my machine.