Lots of us here use water cooled tubes and I for one have no problems , Lots of reasons their cheaper, their imports for one, the tubes are cheaper to make and they cost a lot less. they don't last as long but for the price to replace them they are ok. You can get a much bigger machine and lots more power for less money because of this and because they don't have all the bells and whistles of the big 3, but there perfectly good lasers and will do the same thing as the others lasers they cut and they engrave. Sure theres a learning curve but sounds like you know the basic so you won't have a problem. I would recommend you have a look at Rabbit Laser USA Or Boss laser, or Automation Technology. There all USA based companies that sell imported lasers with USA support. I have a Rabbit and am very happy so far and the support is excellent to date. Not that I needed a lot of support but I did have a few questions and found that it was mostly my errors LOL