This question clearly proves, that any changeling is not able to survive phaser blast. An answer, that follows it explains, that changelings are immune only to metal weapons.
Yet, in "Heart of Stone" we can clearly see a Female Changeling, changed into a piece of rock, that survives many direct phaser blasts. What am I missing? These seems to deny each other.
I assume, that the fact, that Odo exploded (in "Crossover"), after being hit by phaser fire, in mirror universe only has nothing to here. I also assume, that Odo (in "Heart of Stone") set his phaser to "something more than just stun", when he was trying to destroy, what he thought, was a piece of rock.