Actually it does seem unfair and a bit messed up, i mean getting unseals with fc/ds. Fc = sealed 35, pfff, worthless completly, you dig nss for those, much easier. DS = you can get 45 unseal there, but the issure is that EVA is almost at same level. If we take a look on crusader's sixtine spike, then complare to the blade of incantation it only lose in a little bit of HP and few points of accuraccy, and i belive SP regen, which is actually really good if we will have no mediation for a while, but other then that not really good. 2 agi compensate for 2% aspd, in fact in most situation it is identical. It would make way more sense to put 55 unseal there AND dw1 as well. Considering there is also boots+gloves it only make sense that there is more sources to get it.
Do not take it as a suggestion, just some thoughts =D