Verizon definitely has better coverage in the pine barrens. T-mobile doesn't even work consistently at Goshens Pond, let alone in the center of Wharton. When I camp at Goshen's I sometimes have to drive down to where the Atsion cabins are to make a phone call. There's service for maybe a mile or two east of 206 and then again on the other side at Washington's Tavern. In between, and all the way down to the beginning of Batsto Lake, and north almost to the Carranza monument, is a big dead zone. Tmobile is cheap for multiple lines, which is why I have it, but bad for exploring in the woods.
Speaking of Goshen's Pond campground-- the water from that hand pump by the main parking area is both safe to drink and tastes great. I'm normally suspicious of things like that, but my daughter, who likes to play with the pump, once decided she wanted to drink the water. She was really persistent about it and I finally relented, figuring the diarrhea wouldn't kick in until we decamped and drove home the next morning. We both ended up drinking a bunch of it, and it is perfectly fine and tastes better than the chlorinated tapwater you're used to.
That campground, despite being labelled "wilderness camping" is far from it-- you'll see lots of cars as well as the state park police driving by all night long.