The very first time I flew into MSN and landed at this Dane County airport was in 2015, and since then I have flown many times in and out of this airport.
The airport is typically clean and nice to explore around. There's some artifacts in the lobby area before the check in desks. I would highly recommend using each airlines own phone app to do early check in to your flight (up to 24 hours before departure).
This airport does have a TSA pre-check security gate on the right most side, so only use this if you have Global Entry or TSA pre-check (which I'd also highly recommend applying for if you travel frequently.)
Overall, it's a nice and cozy airport located on the east side of Madison. There's never a lot of travelers throughout the week except during peak hours associated with heavy travel days. Relax, arrive early for your flights and have a safe trip!