If i were in your place i would go to a shop which carries plug boots. I would try all the plugs they have and i would get the one that fits better out of the box. It doesn't matter if you get the Nordica, Lange, Tecnica, Salomon, Head or Atomic. They are all capable of winning races and they will help you win. If the Head fits better than the Atomic i would get the Head. Then, if they don't have a good bootfitter who can build the boot for you, go to a bootfitter with a good reputation. You can always go to ANOTHER SHOP where you can see a good bootfitter. Some bootfitters do not sell boots.
You have another option. Go to a reputable bootfitter first and follow his recommendations. This is probably the best thing you can do but if you do not have time to find one right now, i suggest you get the boot first and then go the the bootfitter. Make sure you get the boot in the correct size and you like the forward lean. The Nordica and the Head are more upright than the Atomic. The Tecnica is more forward than the Atomic. This is very important b/c IMO it is better to get a boot which has the stance that works for you better out-of-the-box. If you like to be more upright you could get the Nordica or Head. If you want more forward lean i recommend the Lange, Atomic and the Tecnica. Then the bootfitter will built the boot for you. IMO the winner is the boot which fits better than the others out of the box and has the stance which works best for you.
You are a racer and i am sure you know if you want more fwd lean or to be more upright.
I ordered the RT Ti XS (extra soft). I weigh 155lbs. The RT i tried last year was the Soft which was too stiff for me. If you weigh 170lbs+ i suggest that you get the Soft. The boot comes in a Medium flex, too. But it is too stiff for most people. You may find great deals on Mediums. Don't get them. They're too stiff. This is why nobody buys them.