I really wish they would go all Bami's Cinder on Nashor's

That bonus AP on-hit really meshes well with some builds, even if the full Nashor's isn't so practical to build up to. The total cost gets a bit silly as a core or starter item when it gives little in the way of up-front DPS and doesn't give sustain to combo with the CDR.

I definitely think that if you're building Nashor's though, you're either a champ with already strong on-hits who has a really high cooldown on something... or you build tanky like Diana and can afford to be in range long enough to land hits with it. There's very little in the way of many other mages using it practically otherwise I think. (I guess the AS is the barring point and people would say "Lich's".)