TM Mp5k is awesome, and I can say that from first hand experience. It was my first airsoft gun, and it was great. Hop up allowed you to sail some shots seriously further than you would have though possible with such a short barrel.
However... CYMA has a full metal MP5k coming out that you might want to wait for.
Not for glory, nor riches, nor honours, but for freedom alone, which no good man gives up except with his life.