I see you're right smack between MSP and DLH, so overload isn't going to be an issue for you. If you watch TV entirely from one market to the exclusion of the other, you may not even need a rotor. Hoswever, if you're wanting to DX or do any of that sort of thing, the rotor is of course important. I assume you plan to get "above the trees" as well. I've found that the directions in which I am not above the trees, the trees can really hurt my reception.
A nearby DX'er has always been complaining about the St. Louis stations (135 miles away) being insufferable pests. They don't bother me...but the tree is in the way in that direction. I have the feeling that, as a DX'er, I'll soon learn to start getting "fed up" with signals from that market as well, because my new and somewhat taller tower is almost built, and if it still doesn't clear the tree, I'll have some of the top of the tree cut off. What I gain from St. Louis becoming a "big pest" should be more than offset by the advantage of suddenly having my south and southeast opened up. From the central U.S., that's a VERY bad direction to have blocked.
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