I think I will go with the carbon scissors, for the moment will I only need to cut a little Kevlar.

 My recommendation would still be to get the carbon scissors, as the EC ones still cut lighter weight Kevlar (like you would find in regular carbon/Kevlar fabric) very well, and they will last much longer. If you are cutting carbon/Kevlar day in day out, then the best thing to do is to pull out a couple of weft fibres before you cut the material, and this will allow you to cut just the one type of fibre. Obviously this only works if you are cutting in straight lines. 

I can see there are two different kinds available, one for Kevlar, and one for Carbon. Can you tell me where the difference is? Could I buy a Kevlar scissor, and use it for both materials? I', trying to keep this costly hobby a bit under control, the wishlist is still long..