OK so first cheap compessor is......

You'll have to be more specific in your description of what's happening. If you have large filters (like the big gold Tuxing) it takes a minute to fill that area. What compressor? How long exactly does it take to start filling? Have you leak tested & dead head? This info is essential to getting pertinent answers.
 
I ran a dead head test on my $250 GX CS2 when I got it as recommended. It was about 23 seconds. If you have this sort of data it's great if you think the compressor is not working great. If not, usually the issue is a leak. Soapy water might show you the location. You apply the water as you air up a gun.