There are rumours but I don't know if they're true.
There are two revisions of v2 that I can gather:
First revision - the nand flash chip is soldered directly to the main motherboard.
Second revision - the nand flash chip is on a smaller detachable board which plugs into the main motherboard. A new Sunray remote is sometimes supplied with this revision. I guess there could be a third revision then (ie one supplied with sunray remote) but couldn't say for sure.
I had first revision and got rid of that for second revision. Be aware that some chinese sellers are stating this is v3 but having checked the security chip module, it states v2 and only thing that has changed is nand flash chip as I mentioned.
If there is an actual v3, I'm not certain what has changed/new that wasn't already introduced in v2 revision 2.
A v3, may claim to support original images but some adverts for the current detachable nand version (ie v2 revision 2) state take original images but personally I'm not taking that risk and using clone safe images to be on safe side because going back to original images could increase chance of a bricked box. There are very regular updates to both (most) images and drivers so that's why I stick with clone safe drivers.