Einsteins vs Westcott Spiderlite TD5 or TD6

I should have also mentioned I have 5 Alien Bees, B800s. They are nice. So the question is that would 2 additional Einsteins or 2 Spiderlite DTs will be a better addition? I was the reviews on the Einsteins and they seem like very nice units.
--
Murat