I've never had one snub it and have had good luck bringing around neglected horses with it. TC Complete is pretty close to the Training at 12/12/15 instead of 13/13/13 and I've also not had any turn their noses up at it.
It's taken so long for the local Southern States to get the 14% Racing or Racing Complete so I have just stuck with Training. Filly eats it really well and I put 4 more horses on it and they look great. Feed them about 10 -11 lbs a day and all keeping their weight well and eating it up. Glad I persisted!