Bests & Worsts Reviews from Amazon

So there are a few bad reviews saying the power supply destroys things, so before I plugged it into anything important, I measured the output voltages with a multimeter. The power supply that came with it is Flypower MODEL SPP34-12.0/5.0-2000. The power switch in the cord is not making good contact. If I push it hard to the ON position, it reads 5 V on the red line. When I let go, it sometimes stays at 5 V but sometimes settles at 1.5 or 2.5 or something else. So the power switch is making a shoddy connection and that's why some people say it only works sometimes. Also only one of the ground wires is connected. The other appears to be floating. Not sure if this actually matters or not, since they'll usually be connected together inside the drive(?), but it doesn't exactly inspire confidence. Even when it's connected well, it's 5.29 VDC, which is slightly above the ATX power supply limit of 5.25 VDC. This probably doesn't really matter, since it will droop under load, but still. The yellow pin is 12.28 VDC, which is within the limits.