One model, the one used by HSRI, for instance, I think, is fairly strong on validity but weak on choice. Even if you evaluate based on whether a client reports being given a choice, if every other metric assumes the state's preferred outcome and rewards for it, the pressure is to treat all people with developmental disabilities as if their most intimate decisions are to be pleasing to the people at the Bateson Building in Sacramento.
The common alternative model, I think of it as the JN or LQA model, is to have a deeply considerate and subjective evaluation so cumbersome it typically sits on someone's shelf unimplemented.
A typical Life Quality Assessment was kind of silly because it was so subjective that which day of the week a client was interviewed could alter the entire result. A more valid survey biases every professional in a client's life toward state policy and away from the person served.
So, the question to you all is: Is it better to employ a highly valid system that might counteract client choice or is it better to use a subjective system which honors choice at the expense of usefulness or is there a better or more balanced solution?