If you want the best juicing appliance, as in the one that produces the most nutritious juice, then you should buy a Green Star juicer. There are a few different models in the Green Star range, the cheapest is the GS-1000. That said, it is not exactly cheap. This machine costs over $400. So it is definitely a top of the range kitchen appliance.
The Green Star GS-1000 is a twin gear juicer. Other types of machines include, citrus juicers, centrifugal juicers and masticating juicers. But they are all quite different in the way that they work. Twin gear juicers operate at the slowest speeds and centrifugal machines are the fastest. Typically, fast is good. However in the case of making fresh home made juice, faster speeds are not always beneficial. It is true, that using a centrifugal juicer you are able to quickly turn a bowl of fresh fruit and vegetables into a great tasting drink. But the draw back of higher speeds is that they produce more heat. This can damage the juice that you make by promoting oxidation.
Twin gear machines like the Green Star GS-1000 juicer on the other hand work at much lower speeds. This machine is a 110 RPM device. So it is true that it will take a bit longer to produce a drink with this unit. However much less heat is produced so oxidation of the drink will take longer. This means that there is the potential to get more nutrition from your fruit and vegetable drinks if you use a twin gear juicer.
These sort of juicing appliances are really only for people who are serious about their juice and health. It takes a bit longer than a centrifugal appliance to put the Green Star GS-1000 together and the clean up after use takes more time too.