This afternoon Shellene and I drove to Waco and road the 24 mile loop that they will be racing on for the Tonkawa Ultra Cup races (6/12 hour).  http://www.tonkuc.com/
 
The loop starts at the race hotel, the Atira Hotel and Suites in McGregor.  The hotel does not have a public restroom, hopefully the race organizer will have portable plastic trees available on race day.
 
The first mile of the loop is on Hwy 84, with a limited shoulder for riding on.  After that, the course turns north onto extremely rural roads.  From McGregor to Crawford (a distance of 14.5 miles) we saw one 18 wheeler and one car.  In this section there are two left turns (onto and off of Old McGregor Crawford Road) where I was worried about traffic before we road the route, now the concern may be oncoming bicycles and not cars.  Once we got to Crawford it was small-town traffic through town and then a turn onto Hwy 317 (North Lone Star Parkway).  The two miles on this stretch of road had a good shoulder, and the traffic was not bad.  The road off of Hwy 317 is Steinkamp Rd, and it comes to a t-stop (with stop sign) at Old McGregor Crawford Rd.  This stop sign is at the bottom of a climb, and the climb out it probably the steepest on the route.  A nice leisurely stretch of road took us back towards McGregor, on the actual race day about 1 mile of this section will have racers going in both directions.  We re-entered McGregor from the north side, and the road went quickly from smooth chipseal to potholes in the turns.  This was the only place where the road itself could affect the race (especially at the end of the race with tired riders).  The loop ends with a mix of Hwy 317 and 84 for the last mile, the traffic here was the worst of the course, and it still wasn't stressful (but then I used to ride in Austin traffic).
 
When you look at the posted profile it shows 276 feet of climbing, my Garmin recorded 541 feet over the 24 miles.
 
Other than the potholes on N Main Street in McGregor, the route was mostly smooth chip seal.  Traffic was very light to non-existent everywhere but McGregor, and that was not bad.  The route is beautiful, but exposed to the weather (the photo they have on the website of the rider descending down a tree lined road was not taken on the course).  Also, if you are allergic to corn, this route may not be the best, that is the crop of choice at this time.
 
If you have ever considered racing a 6 hour race, this might be the best starter race with regards to elevation gain and traffic conditions.
 
My Garmin file:  http://connect.garmin.com/activity/328293910