My reaction to the OP's question is "Why bother". All the cheap compressors are junk!! At least buy one made in Australia. Will they cost more? Yes. They will last and provide good service. But, they will still be slow. The Warn VTC is the way to go but have the drawbacks of expense and finding a space to mount. Still, the VTC is awesome and I love mine. But if you are still learning the "you get what you pay for" mantra, you will never listen to my advice.
And how do you determine value? The only thing I know is buy cheap and get junk or buy expensive and get quality-usually. How does one figure value if you are wasting your money buying stuff that does not work well or fails. If you you know the secret I would like to hear it. I don't enjoy spending large amounts of money either.
not everyone is willing or capable of buying "expensive" for every endeavor they undertake, nor should they just for they sake of spending the most possible. for many people overlanding may be just one of many hobbies, or it may be something that they are just starting to get into and therefore do not wish to devote a small fortune to accessories yet. the OP's question is realistic and one that i'm sure many people have had.
value is defined as "relative worth". could be relative to other similar priced products, or to other items you might spend your available money on, or any number of ways in which something has "worth" to you in comparison to other things.
- for me the sub-$100 MV-50's worked flawlessly for several years and then slowly began to die. it performed just as well for a couple of years as compressors costing 2 or 3 times as much. therefore, i found it to be of great "relative worth" as compared to the other compressors in my capable spending range at the time.
even within the $400+ range of compressors one can still determine "value" based on which qualities are the most important to them and which product delivers those qualities for the least cost.
"you get what you pay for" is a great adage. however, if you have no concept of value, then you will no doubt learn that "a fool and his money are soon parted".