Which exhaust system provides the best level of increased HP + just the right exhaust sounds. I like the looks of the Hamann system, with the upturned exhaust tips. Is there a problem with water collecting in there?? I don't like looks of the single larger pipes a la Hennessey. Anyone got insights into what Dinan will have?? I'm thinking of waiting until their CAI and exhaust components are both ready, and do them together. Thoughts??