This review is for the 20 piece kit. The kit itself is mostly useful, especially if you are setting up a new compressor. I didn't end up using most of the parts beyond setting up the air hose & little attachments. But the main issue with this kit is the hose. When I buy a hose, my expectation is that the listed length (25' feet) will be the distance that this hose reaches. Wrong. The 25' foot listed length seems to be the amount of very rigid plastic that this hose is made from. The reality of it is, that this hose will only comfortably reach about 6 feet. I might be able to stretch it to 10 feet. But I'm worried about breaking the hose. If by some miracle I did stretch it past the 10' foot mark, I highly doubt it would ever coil neatly again. With this hose, there is no possible way I could reach anything 25' feet away without resorting to black magic.

Works pretty well. Used male and female QDC on hose, and two male QDCs for the blower and tire inflator, leaving three spare male QDCs for any other accessories you have (one of which with female NPT threads), assuming you don't need one for your compressor.
Air pressure gage is cheap, not sure how accurate it is, but seems consistent at least.
Fittings leaked air even after tightening 1/2 and even 3/4-turn after hand tight. Teflon tape resolved that though.
QDCs are difficult to attach with high pressure, so be sure to adjust the regulator before connecting them.
Tire inflator is a bit awkward, and near impossible to get on my motorcycle's rear tire valve. That may be just an incompatibility with my bike, but something to consider.

I haven't used the blower or ball inflator attachments, so I don't know how well they work, but I can't imagine them not working with how simple they are.

These fittings and accessories get the job done, and for the price paid it is not a bad deal. They feel light in the hand and appear to be stamped together as opposed to a single modeled component :This makes the product look and feel "cheap". However, I have filled up 8 car tires, and ran a framing gun for a total of 36 hours since I bought this kit and they have not failed me yet. Since the price is so low, I would say that you get what you paid for, but it will get the job done. If your a contractor I would suggest paying more and getting a more robust set, but this is perfect for the average home owner.

The blow gun/trigger piece will not seal tightly on the hose threads. Everything else seals tight so it's not the hose threads. But the air gun leaks air at the base at a fairly substantial rate. There's a sticker on it that says "90 PSI", but even at 25-30, it's a pretty good leak. Unfortunately, this was one of the main pieces I need in this set. I expect to use it regularly, and it's by far the worst piece in the bunch.

It's worth noting that everything else seems well built - the other pieces seal tightly and all except the tapered nozzle feel very robust and well made. (The tapered nozzle feels plasticky like it might not last, but I don't expect it to see much heavy duty.)

I do not feel ripped off given the price, but the bottom line is I think you could get a better set elsewhere for a comparable (or maybe slightly higher) price.

I really only needed the air blower nozzle, but as a cheap add on item why the heck not have some other components lying around. The quality control isn't the best but you already knew that.