I have all of the wheels sizes for particular purposes and conditions.
XC race - Salsa Spearfish FS 29er
Fatbike/winter racing - Mongoose Vinson rigid 26
XC singlespeed fun - Specialized Carve SL rigid 29+
Trail/stupid fun - Canfield Brothers Yelli Screamy HT 27.5+
barcrawl/grocery getter - Walmart BSO FS 26
if Wisconsin had any serious enough terrain for a long travel DH bike I'd probably go with a 26er.