@SekiryuuteiDxD: Wrong forum and haru should stomp Natsu really hard.
I forgot to comment since I'm a fan of both series. Pre Symphonia arc Haru Glory will lose to Natsu. With Haru Glory mastering all of his Ten Commandments at the end of Stellar Memory or the final arc in the manga, he will definitely beat Natsu easily. I haven't finished Rave Master, but Hiro Mashima's work is different with Fairy Tail and Rave Master. In Rave Master, the characters start off weak, but they get stronger. For Fairy Tail, it's hard to say especially for Natsu. Natsu is like Ichigo of Bleach. He is strong at some points, but he loses easily to opponents that he has beaten in the past like Laxus.
Good match up by the way.