statues of Daedalus

Was Plato right to say that knowledge is better than true belief?
The difference between knowledge and true belief is that knowledge is justified and is not obtained through "luck".
I have already considered whether knowledge can be said to have intrinsic value. The general consensus I think is that is is often difficult to identify what (if any) intrinsic value there is to knowledge. I will therefore try and answer the question by considering whether knowledge has, by its nature, greater extrinsic (i.e. instrumental) value compared with true belief.
Pritchard, along with Plato, seems to think that knowledge does have more instrumental value because it is less likely to change. I think that the ability to justify true belief must also add to the level of conviction of the believer. If we are more confident that our belief is justified, then we are more likely to "leverage" this knowledge and thereby exploit its instrumental value.
For example, David Hume points out that we we cannot (and should not) take a sceptical view of causation in relation to "everyday life", since we would be paralysed by uncertainty. By justifying our beliefs about cause and effect in terms of scientific theories which are supported by evidence, we can overcome this scepticism and thereby provide support to the many "rules of thumb" which we rely on. In science, the "natural laws" which we have developed provide a framework by which we can predict the future and  understand (even control) our environment. I see these natural laws as a type of justified true belief (i.e. knowledge) which compares to a world view which comprises merely true belief, where we would not be able to benefit from scientific advances to anything like the same degree.