To be honest, between levels 250 and 350 I built Fabulous Legs T2, Boots of Haste T2, Falcon Battle Axe T1, Terra Helmet T2, and Phantasmal Axe T2.
Now, with the multi-task hotkey, the helmet tiers have become very interesting for the EK. But you might ask me: which of these items do I have today? None.
Currently I'm EK level 520 and I had to sell all my items to buy the full EK set. I lost a lot of money on that, and my experience is that you shouldn't spend too much money on tiers if you want to level your character up to get the full set. At the end of the day, we change equipment a lot in the early game (between levels 100 and 400).
My other MS and RP characters that are close to level 250, I don't even think about spending money on tiers, it's really an investment for the final sets.