In sixteen years I've owned six different compressors. They fascinate me as much as the PCPs they fill. I've spent more time researching, comparing, buying and selling compressors than I probably should have. I've owned two models of the Shoebox line, a used Bauer Utilus continuous duty compressor, an Alpha Carette, and now I'm using a Daystate LC-110 which is a 115 volt compressor made by Coltri.
The best of the best on a price is no object basis is the Bauer, hands down. However, a Bauer is overkill for most users. It is the finest quality but it isn't the best value. Using automobiles as an analogy, a Rolls Royce is the best luxiury car and a Ferrari or Lamborghini are top of the line sports casr, but they aren't the best bang for the buck. The same applies to compressors. If you manage a fire department fill station, a paintball shop, dive shop, or a shooting club then a Bauer is the best choice. But most of us don't operate a compressor enough hours per year to require a Bauer. Bauers are premium priced and a new Bauer is overpriced compared to other brands. If you want a Bauer, I suggest checking out Craigslist in South Florida or Ebay and buying a used Bauer that has been refurbished or lightly used. That's where I purchased the Utilus. After using it for 3 years I found that I wasn't running it enough to justify its size and cost. It sold it for the same price I paid to a local paintball field.
Look at the other end of the price spectrum. Many buyers look upon compressors as a necessary evil and therefor cheaper the new price the higher the appeal. That's why the Yong Heng class of $200-300 compressors have mass appeal. But they are a poor value because of their minimalist construction, shoddy materials, questionable support, and short term life span. Unless you enjoy repairing it frequently yourself, and don't mind that it is likely to die at any time then avoid them. Their failure rate and overheating issues from being over driven makes them a poor value. When I start my car or turn on my TV I don't want to have to hope it will work for me. That's the same way I feel about a compressor.
Another popular compressor line that IMO is overpriced and a poor value is the Omega line of compressors. They are very expensive for their limited durability and longevity. They are electrically and mechanically complex compared to a dive compressor. Anyone who follows the forums knows they are sealed with rubber o-rings which are difficult to replace by the average owner. They tend to have a lot of electrical, check valve, pressure failures from o-ring wear, and cooling system leaks. For the money they don't have the durability and longevity of other compressors that are in the same price range.
The state of the art is constantly changing. The LC-110 Daystate is the best value in compressors today. It is quiet running, air cooled, has automatic shutoff built in, It's built around a true dive compressor head with 3 stage compression using roller bearing pistons with steel rings for longevity. It runs on a household outlet and can be moved by one person. All it requires is oil changes and an output filter as an accessory. For the typical PCP owner it is great value if fill speed, reliability, price, and durability are all considered. It mystifies me when guys don't blink twice at the price of a $2,000 air rifle but won't spend money to own a quality compressor.
In conclusion, best price no object compressor is a Bauer. Best value compressor for a PCP single user today is the LC-110 by Daystate.