I've heard mixed reactions as well. I currently have the MRT rails and just haven't had the time to install them.

One plus about the Perrins is that they are a complete set (from what I have heard), where as the MRT set requires you to do wome modifications to the existing fule lines.....which is no big deal since I am redoing the entire underhood fuel delivery system via SS lines, AN fittings and a larger fuel filter.