Dexron VI in Dexron III application

[Orionaut]

Has anybody tried using DexVI in a vehicle that was originally specified for DexIII?

I know that DEX is supposed to be backward compatible but I was wondering if anybody has had any experience of doing such a swap and can report on whether it made any noticeable difference.

It is also worth noting...

Dexron-III licenses expired permanently at the end of 2006, and GM now supports only Dexron-VI fluids for use in their automatic transmissions, although fluids asserted by their manufacturers to meet Dexron-III standards continue to be sold under names such as Dex/Merc. These fluids are not regulated or endorsed by GM.