This has been a fascinating thread to watch. Thanks everyone for the insights.

During my original purchase, I felt like I had excellent support from Camaster. I really haven't had any problems with my machine after the first 6 months or so - and so I haven't tested their support infrastructure these days. They haven't been the most accessible for questions concerning upgrades - often taking a few weeks to respond - but I guess that's not surprising given that I am a pretty small fish with an old machine and upgrades really aren't their thing. Ditto with getting quotes - long delays - but there isn't an emergency here. It's been disappointing to see the control infrastructure of my machine dropped by the company so soon after I purchased it but that hasn't prevented me from using the machine without problems.

Perhaps the issue is that Camaster (and a few others) straddle this line where they focus mostly on selling big machines to professional customers but also have a foot in the small machine to private consumer market. I would imagine the process of selling and supporting a $50,000-$75,000 5x10 ATC machine to a business is pretty different than selling a $8,000 machine to a guy in his garage. Us "guys in the garage" like (and are used to) the options of incremental upgrades and tweaking over time because our livelihood doesn't depend on this machine churning and we like tinkering (and have limited budgets). I suspect a business wants a turnkey workhorse machine and if they outgrow the capability it's much more efficient to just upgrade the whole shooting match and replace rather than waste time tinkering. Maybe the consumer oriented CNC companies (like Axiom for example) have a different model of machine upgrades (or maybe not...).

At any rate, the take home message appears to be - upgrades are probably too expensive and too complex to consider. If I can find someone interested in buying my 48x48 then I'll sell it and invest in a smaller more modern machine but if not then I can continue to enjoy using the fine machine I currently have.

Thanks again everyone.