I actually think they have been pretty bad in the mid-tier pitching side of things. They gave bonuses >$250k, but <$1M to Victor Vargas, Carlos Betancourt, Israel Puello, Hsin-Chieh Lin, Joalbert Angulo, and Fernando Ortega in the Klentak years and have very little to show from it.
I think by the time you are in that range you are much better going low bonus for either pure projection guys or going for the guys that pop up at 17 or 18. It isn't that you can't predict anything on 15 and 16 year olds, and more being open minded about signing older arms because we see even domestically, there are dudes who were bad HS pitchers who suddenly don't come into it until 19-22.