I'm curious to see how the radishes do planted that thick. Ideally, you only want around 3lbs per acre for them to produce the huge tubers (12-18in long, and 5-6in wide) that bust up hardpan. Planted that close I suspect they will produce pretty small tubers. It's good you planted them a bit early... they also need some growing time before it gets cool to produce the large tubers. As far as the greens themselves, deer hammered mine last year which was the first year I ever planted them, you won't be disappointed in that area. They will certainly grow faster than deer can browse.
post an update in early November before first freeze. Pull a few up by the roots and snap a couple pictures.
Oh, one more think about the radishes. If you don't end up with a couple inches of tuber above soil line, winter freeze may not kill them and you can end up with a lot of volunteer new radishes in the spring after they bolt. Only an issue if you are planting a summer plot next year.