I have (2) wireless units I bought at Walmart. Not sure the brand, but I think it's "The Backyard Grill", $15 each.
I've only used them a couple times, so I can't speak for longevity, but they work great. I have the receivers sitting in the house while I"m doing other stuff and can see the temp at any given time.
A man wearing a helmet defending his country should make more money than a man with a helmet defending a football.