[Crw-talk] Vacuum chucking questions

[John & Donna Griffiths]

Hello all, I have some questions:

How satisfactory are the vacuum devices that run off an air compressor?  
I'm told they are very loud.  Is a vacuum pump a better direction to go?

How reliable are used vacuum pumps?  I see them on eBay for about $45 or 
so.

Are the pumps used by HVAC technicians to draw the air out of air 
conditioning systems satisfactory?

John