I've only fished it a couple times so take this for what its worth.
It only receives spring stocking and the stocking spots are heavily fished. There doesn't seem to be much holdover trout even after only a couple weeks.
There has to be some holdovers though and I would think those that survive the spring probably have to find thermal refuge (springs, feeder creeks) and faster (oxygenated) water.
There is some nice looking water like you say and there are also some wild brookies in addition to the stocked fish.