Ray, I've tried a lot of PUPS in mid position, basically trying to get a good quack combined with the bridge or neck.
The HS-2 single coil is absolutely great for that, because its really crisp. Its also the only middle PUP I've found to be usable on its own. Others have been too midrangey and indefinite.I have an AT-1 in bridge, and of course, it doesn't really compete with that, but I use the AT-1 split a lot of the time, and they balance well. I have a Seymour Duncan "Hot For Tele", with cover removed in neck position, and the HS-2 balances well with that, too. I've got it set pretty high, but string pull hasn't been an issue.
Hope this gives you some idea.