I agree with washnshine - different thought processes for different people. I can see replacing if the new machinery was better -- however, I've driven through quite a few 'better' machines throughout the years and haven't seen any difference over the ones I've got besides a new look and new 'show'... I'm not sure what actual improvements have been (or can be) made to the actual machine besides cosmetic/glitz. And as I've said, I can get a new look and glitz for a lot less - I can redo all the graphics, add lights, etc for a fraction of the cost, customers think it's a new machine and I can raise my prices (actually did this a few years back). Not sure how new ones are faster? And not sure what the 'programmable' part is .. the gantry makes 'x' amount of passes, some faster some slower...not much more you need to do? As far as repairs, the first year or two is nice, but then you have the same repairs as an older one, it's still the same hoses, swivels, and motors -- except the new one probably has a lot more electronics that makes you more dependent on the manufacturer.
I'm really not trying to milk anything -- this isn't a foam brush head that I'm trying to leave out there until the last 10 bristles fall off. My whole philosophy is to keep it simple, so when I can replace something so it's better for the customer/makes me more money/and is easier on me I definitely do. But when it still performs as good as a new one, when I can make it look like a new one, and the downtime is comparable I just don't see the reason. And the reason manufacturers sell new Automatics is to make money .. not necessarily because they're better.