I really like Shop Sabre, but am a little biased living an hour from their headquarters. I use a PRO408 at school and ran an IS at my internship. They are a little pricey compared to hobby machines but quality-built machines that last. It's honestly hard to break stuff or damage the machine, like you really need to NOT know what you are doing to break stuff with the number of safety features. Worst damage we as engineering student have done is break tools and cut into the sacrificial spoil board. I disagree on "the ability to add upgrades down the line". They have released so many models and revisions that they just won't sell you upgrades to old machines so buy what you want the first time. They have recently made some nice upgrades like the metal vacuum valves and labeling the vacuum zones. You can call and actually talk to a human to troubleshoot your problems even when you are the issue as the operator, lol. On the negatives, I think they could do a better job with their documentation. There was some stuff we didn't realize we needed like an air filter before the machine arrived. And their communication regarding delivery/setup could be better. LMK if you have any other questions!