I live in SC, so I don't know how my experience will relate to IL. If anything, maples may grow better in IL than SC (they do in NJ and OR). An Inaba Shidare I've had for 15 years or so is now about 7 ft tall. I made a graft from that tree and it's growing at a friend's home. That tree is about 5 ft tall, but it has also spread and may be about 8 ft wide now after 12 or so years. A couple of times already my friends have asked me to prune it because it grows all over the azaleas next to it. I expect that after a few years the maple and the boxwoods will be competing for space. Red Dragon is a newer red dissectum that holds its color better than Inaba here in SC, so I prefer it to Inaba. Hope this helps. Tom

I agree with Tom. There are JM cultivars that don't get quite as huge as Inaba Shidare. I've seen one 20 ft. tall and 15 ft. wide. Red Dragon is a great choice.

Thank you for your perspectives. I see you are both in much more mild climates than I am and wonder if you can direct me to gardening blogs where I can find experiences in my zone with this plant. I am not into gardening at all, so I don't have these resources at my fingertips.