Man my wallet is crying everyday telling me not to buy this, but it's getting really dificult to pay atention to it everytime i look at the renders!
If you buy it, you will have a very nice set.
If, later on, you have a keycap set that is crying out for blue modifiers - you have some.
Plus if you really need to sell it, it's pretty certain that you will get your money back on the set.
If you don't buy it, you will probably end up looking through classifieds, hoping someone will list a set for sale.
I have the original GMK purple modifiers - they spend most of their life sitting in a box, but they are there if I need them.