null-modem cable
For the firmware update, don't forget to use a null-modem or crossover cable.
My Mercury II may have come with one, but I used a cable I'd made for another receiver.
The Visionsat takes a straight-through cable, if you don't use the thumb-drive.
One thing worth doing, is put a sticky label on the bottom of each receiver, with a reminder of which type cable it uses, and the default factory password.
I think 0000 is correct for both (but someone will post if I'm mistaken).
Speaking of labels, I also put a colored dot next to the coax connector that goes to the LNB.
It's so much easier when changing receivers or wiring, to not have to drag out a flashlight.