Those boxes are made for pulling a single, maybe two runs. At least that's all I've found them good for. Some are probably better than others I suppose but I can't tell you how many times I've kicked the hell out of one because I was half way through a pull and the thing got all tangled up. "Unreel", "Reel in-a-Box", whatever, doesn't matter. So I decided long ago to prefer my cable on reels and if you are going to do a project that requires any where near 250,000 feet you'll be pulling your hair out (not wire) with those boxes.
Get yourself a couple of these. You can get a lot of 1000' reels of two pair on that.
-Hal