Don't know about Mille GT but Equipe RS S9 is pretty good.
Going on a tangent, here's what I gathered from the 100+ page Assos thread in weightweenies:
Mille GT - Comfort Fit, pad slightly further forward for a more upright position. Consider this every day kit.
Equipe RS - Racing Fit, more compressive / aero. Pad slightly further forward for a lower position on the bike. Consider this 'fast', 'race' or 'special day' kit.
Cento 113 - Comfort Fit, pad slightly further forward. More tech than Equipe and Mille. Luxury, cosetting kit for those who want or need more.
Mille GT is the cheapest and is everything most people need. Superb products with one of the best chamois available. Materials are world class and the cut is slightly more accomodating than out and out race fit. It could be considered training kit for those racers riding mega miles, and best kit for the rest of us. It works with the other products perfectly too.
Equipe RS is up a price point, because the technology and materials are more expensive. It is our race proposition and aero.
Cento / 113 takes the materials and tech from Equipe, and applies the fit from Mille GT.