Cheap or low cost - Quality or Quantity - Your choice
Had a Quick Air III for several years before it blew up - it was cheap junk
Now have three 12 Volt Viair systems
There are several better 12 Volt compressors - check out the Jeep forums
Depends on what you expect from it and for how long
That said Viair is good enough for most applications
The Viair 12 Volt system I have now in my rig includes a 5 gallon holding tank and is capable of 150psi @100% DC - fills tires - powers air tools - etc....
It gets used almost daily when we are out enjoying the outdoors
As said above make sure it is correctly installed