I'd avoid the discone unless you really need the very broad bandwidth or the capability to transmit. They have no appreciable gain and there only strong point is the broad chunk of spectrum they cover. A good antenna with gain will outperform a discone in most places.
I've got and old Diamond discone I scored for free and I use it on my roof top for 2 meters. It works just fine, but if I was buying a new antenna, I'd go with something like a Diamond X50 or similar. I'm not sure what the radiation pattern is like on the discones. It works well enough for me, but I'm in a fairly small valley, so I don't need much range. You being in Iowa would make me think something with a more known radiation pattern might be a better choice.