Yes they are fairly to repair once you know how. Just don't be attempted to wire probe these as there are tiny rubber check valves. Also you don't use harsh cleaners and strong compressed air. I do recommend using an ultrasonic cleaner on these if you do several a year. Well worth the expense of the ultrasonic cleaner. Besides they are safer for the user as you are not exposed to dangerous cleaners. A simple soap and water solution is all I use in them.
Other than that most cubes are repairable but there will be exceptions where corrosion is too bad or you come across a leaking needle seat or check valve.
And as Tyler mention the rotary barrel ones are harder to get to working correctly for some reason once they cause problems. Still working figuring out what I am missing on them.
