Rossier is generally a good bet for power, and Charlie is great to work with. As far as my personal preference on exhaust systems, I can´t stand the look of the Barker´s system. Even if it made 5hp more than my system and costs less money, I wouldn´t buy it. Some people really like it, and that´s fine. I just don´t. I´m not really a fan of the HMF pipe, either. They´re not terrible, but they´re loud. Just not really a pipe I´d consider buying when there are other choices that I like so much more. The Monster system, I like how it looks, but it really reminds me of the Duncan Fatboy4 pipes. Not that that´s a bad thing, but I´d rather have something that appeals to me a little more on an aesthetic level. The Dasa, while it looks excellent, and sounds great, it´s simply too loud without the quiet core, and with the core installed, power drops off. The FMF pipe is really nice looking, but I don´t care for how far the pipe sticks out the back. Which brings me conveniently to my favorite... Yoshimura. I´ve owned quite a few quads and all of them except one (400EX) had aftermarket exhaust, and in my opinion, the best fit and finish and overall quality was shown in the Yoshimura systems. I know that some LT-R450 guys had problems with their Yoshi stuff, but I´ve always had good luck with mine. So, out of the pipes discussed in this thread, I´d probably pick Yoshi every time. Good luck with your choice.
