I Bought The Cheapest Mag Starter on Amazon 

Yes, it does have an on/off switch on the side. So far, the mag starter has performed wonderfully and I haven’t had any issues regarding it. And the switch does work, I throw both the switch and breaker when I’m not using my compressor. I’ve accidentally forgotten to turn the switch back on and wondered why my compressor doesn’t work for a hot second!

Thanks! And from 0 psi to 150 psi it takes about 6 minutes to fill my 80 gallon tank

If you watched the video you’d see I pointed out where the incoming 240v comes in and where the wires go for your motor. If you’re having trouble with the pressure switch, it’s wired under the thermal relay for the in and out. Your wiring for the pressure switch may and probably is different then mine. Depends on make of the switch. Look at the wiring diagram. One wire goes out to the switch. One wire goes from the switch to the other terminal under the relay. Make sure to ground it all. Remember it’s 240v single phase. Two hots and a not. If you cannot figure out the basic wiring between the wiring diagrams and this video and comment, call an electrician. You do not want to be on the receiving end of 20 amps of 240v.