HMMMMMMMMM, Hey Kev, How much did you say you paid for those?
$9.99 is tooooooogood a deal.
Take a sharpie marker and number each base and corresponding receiver. They are each on their own frequency. I don't know how many you can use at once before you run into problems because I've only ever run 2 at a time.
As to probe problems, be sure not to put the cable where it's exposed to extreme heat, that can ruin them. Also, make sure not to immerse the probes.
You stole 'em Bro, great score!