MX2 is the best thermal paste at this point in time!
I have used both and after using MX2 i prefer it.
As the package says"8 year durability!"
non bleeding, NON-electrical conductive and "metal-free', non corrosive, non-capactive (a biggie!!), non-curring.
Do not remove and replace your coolers every 6 months. you're flirting with problems and damage to your attachments.
It's a falacy!