Which nebulite should I mount on my weapon?

1 sec invincibility doesn't work until you are actually hit, and if you get super KB'd back, you'll stay super KB'd until your invincibility runs off (been told this by 2 persons on my BL already, so i'll state it as fact until i actually test it).

Can confirm this, have +2 sec iframes on my overall. Iframes are nice for Pot Lock/Seduce and JQs though.