We bought this system purely to make distilled water.
The quality is very good, and it's easy to set up and use.
The only thing that needs "fixing" is that the condenser is far too small and the number of turns in the "worm" is far too small. With water distillation, the efficiency is quite poor because the steam is not cooled as much as is needed in the radically undersized condenser. With the factory condenser, 60% is the best efficiency I could get.
I added a second condenser with 20' of copper in a 10-gallon bucket. With the added condenser, the efficiency is over 90%.
When used for alcohol distillation, the small condenser pot and worm might be good enough at the lower temperatures. But, as I said, my unit is dedicated to water distillation only.
Lastly, I'm sure the info is someplace on the Vevor website, but it would be nice to be able to easily find replacement parts like gaskets and such. Then again, I don't need them right now...just looking ahead!
Overall, a good product that I would recommend.