Okay, this is NOT an unbiased opinion because I tried the 6s in a pass around and did not find it to be a superior shave to any degree. I found the head to be too heavy and bulky, the shave to be average at best for the plates that I could get a decent shave with, and didn't like the fact that folks call it adjustable when you just have a razor with different base plates, not unlike the ATT, which was doing it a long time before.
Having said that, I will speak of the Variant. of the "modern" adjustable razors, I have shaved with the Progress, Variant, and REX. The Progress gives a slightly smoother shave than the Variant and the head is not as bulky and easier to maneuver. The Variant has the advantage of having a better handle (with the grip), having an adjustment dial made of metal, and comes in colors. Overall, it does give a comfortable shave and you are able to dial in different settings immediately so you can go with a high number for WTG, a lesser number for ATG, and a different one for XTG. You can also go in between numbers like a 2.5 setting, which is something you can't do with a Gillette. Of course the same could be said with the Progress. In the end, for me it came down to the build and design which I liked more with the Variant for the same price.
Having said that, the REX is in a class by itself and a totally better shaver than both, but it does cost more than twice the price of both combined.