Thinking of exhaust mod

I have been reading about h-pipes and x-pipes and am very impressed. Especially with the x-pipe design. My Duster currently has full straight duel exhaust that was installed in 2006. I was debating about having an x-pipe welded in the current system. But now I am thinking about doing an h-pipe. My biggest concern is the sound. I have read the x-pipe design quiets down the tone whereas the h-pipe makes it sound more muscular and louder. Is this true? I would assume welding the h-pipe in would be much cheaper. My engine is a mild 318. Right now I am running 318 manifolds but plan on having 340 hp's in the near future. The mufflers are from midas. I forgot the name of them though. But I really like the sound.

So would an h-pipe be an effective mod to my exhaust? I know there are people here who have switch from nothing to one of these designs, what are your thoughts?

All info is appreciated. Thanks.