Ultramaxxed, buy or not?

[liborlad]

Mike
I've been offered the chance to buy one, of a freshly minted set of 25 Ultramaxxed tranny gears for the Emaxx. The price is $200 which includes free shipping worldwide and no taxes. What's your opinion on this? is this a worthwile upgrade? Is the increase in rotational mass a major issue?
I'm running the 10L/9918 with Gmaxx CF and UE suspension. Haven't upgraded the diffs yet, will be buying the UE 6 or 8 spyder in due course. I know I should really do the diffs before the tranny (have already got UE idlers) but maybe this is an opportunity I should not pass up.
Other opinions and thoughts on this would be appreciated.