I very much like the ability to scroll and keep the headers at the top. I even requested it specifically not long before you added it. That's great.
Unfortunately, I'm stuck with IE7 at work (I work for the state, they'll migrate to IE 8 when IE 11 is out), and in IE7, the scroll wheel doesn't work when I freeze the headers. So I either can scroll, but not keep the headers visible, or have to scroll with the vertical slider. Bummer!
Is this on your fix-it list? Please? I'm sure there's a lot of us, many of us on the verge of suicide if this isn't fixed immediately. :)