If i had a century hakw pro 30 and converted it to a fifty what could i expect? Would it be as good as a normal 50 or would it still be lacking in performance in comparison to standard 50's. Any help appreciated.

Depends on what you mean by convert. If you just get the motor mount and drop a .50 ito it it won't work well because the gearing is different. Gear it and put a decent se of fiberglass blades on it and it'll rock. Will it be as good as a EVO or Titan? No, but at half the cost you won't be worried everytime you try something new.