Whats your opinion on the final fight scenes in Transformers 3 (spoilers contained)?

i thought the fight with sentinel prime was really good but the fight with megatron was weak..i dont get how megatron kicks his *** in 1.. in 2 its mostly equal till the end and in 3 optimus destroys him in 2 seconds but i would of like to see megarton kill sentianl prime it doesn make optimus like invinseable but overall it was a great movie.