That is a great question, and it is something that I have thought about a good deal.
The watering demands and the sprout and pout that you mention are major factors. Fatigue, worry, and unforeseen complications get very real after 30 days of grinding. It is a big commitment, so it is good to know what you are getting yourself into with a KBG reno.
I don't know enough about turf practices in Michigan to advise you specifically. I can say that if you haven't done a reno before, it would be best to try something that establishes more quickly, such as PRG, so that you can practice and learn the ropes.
For those of us in the transition zone, KBG becomes far more challenging. The humidity poses such a risk for fungal infections with the frequency and duration of the watering schedule that it is a daring exercise (though some forum members are having success in their efforts to grow KBG in the transition zone). Some cultivars, such as Midnight, handle the heat better than other KBG varieties.
When you consider KBG's ability to repair and spread, it does seem like a no-brainer: Big front-end cost with a better payoff in the end. I tend to agree with the way you are thinking about it.
By the way, you can use a pre-M when overseeding/reno with fescue. Tenacity is a good choice. Seed down and Pre-M on the same day.