Yeah as the guy said above go see wht your options are. All those boots are pretty much the same so it's only really one fit option. Unless you have been fitted for it it may not even work for you. Go see what shape you need and go from there.
Ask yourself, Do you want a soft or hard footbed?Do you need the 10 flex, or would you be happier with the 8? Do you like the original shell (konflict) better than the new one with rubber soles( first chair and seth)? Lastly, how resourceful do you want to be?...as you could buy the first chair and an additional 8 tongue, and a soft footbed for the price of a seth.