Juliasb, one thought that came to me is that if this machine is to be computer guided and still uses a CD, chances are that it will require an older computer (with CD) that will likely have an operating system that is no longer supported and thus could introduce virus, etc onto the computer (i.e. Microsoft Vista) so computer guided feature may be short lived. You don't mention hand quilded free motion but if it works well for that it may be a good investment. I would check first that basic maintenance parts are available--some things just wear out--needle screw, check springs, etc and if those can't be replaced then the machine is worthless when something goes wrong. Lots of questions to ask.
Battle Axe--my machine is handguided and I've thought about add computer guided--but with my Gammill it's still out of my reach. My friend added IntelliQuilter to her APQS and likes it fine but that was also pricey. Maybe you could sell on of your LA and add a less expensive computer system to the one you keep.