I would have to say the Battle for the Belt at Kansas Star Casino in Mulvane, KS held by Maize is the toughest tournament. There are some studs from many different states showing up each year, and it only keeps getting bigger and better. The venue is outstanding, and it is very well ran.
It comes with great regret to say the Wichita Classic has fallen in a huge way. Sadly, I would not even rank this a top 3 tournament in Kansas now a days. This says a lot considering this tournament was the toughest one around by far a decade ago.