You can buy one for each or one to do both. Polder sells a digital probe setup that will monitor pit temp and meat temp. I have never used one so I don't know how well they work. I use a thermopen for spot checks, best money I ever spent. Left it in the rain and had to but another.
FEC 100--Sold and sorely missed.
2 Weber Kettles
Eating and sleeping are the only activities that should be allowed to interrupt a man's enjoyment of his cigar---Mark Twain