The V-7 isn't banned because it was the original 7x7x7 cube, so it doesn't violate this: Since the pillowed 7x7 is the original, the basic concept of a 7x7 is pillowed. Also, banning the V-cube would place a monopoly on 7x7 by SS, which I personally think would be very unfair for those who either don't want an SS or Already have a V-cube. Also, If the V-7 was banned since the beginning, there wouldn't be a 7x7x7 event, since there would be no legal cube when it was introduced.
I agree that the V7 it is not enhancing the basic concept of that puzzle, but not that the basic concept of a 7x7x7 cube is one that is pillowed. The V7 was the first commercially produced 7x7x7 cube, but probably not the first one ever. That said, I think that the basic concept of a puzzle has nothing to do with the first puzzle of that order that was made.
Current enforcement of regulations would suggest that pillowing puzzles is an enhancement of the basic concept of that puzzle. I think that we should not be making an exception from that for the V7. I think that pillowed puzzles should be allowed in all events, since I think that pillowing a puzzle does not enhance the basic concept. In my opinion, the basic concept of a puzzle does not involve how many pieces are visible at all.
There is a precedent for the banning of puzzles that people want to use. People had bought stickerless cubes for BLD, so there is clearly no issue with not allowing people to use puzzles that they had bought for an event. I think that that was unfair. People have bought lots of stickerless cubes, and (in the wake of the clarification) have decided to take them apart and assemble sets of cubes of a uniform color will still have to buy stickers. If you buy decent quality stickers, that can add up to quite a sum of money. You shouldn't argue that people that have bought the V-7 should not be required to buy a new cube, if you are going to argue that people with stickerless cubes should disassemble, reassemble, and then sticker all of their cubes. That is really unfair.
I don't want a monopoly, but if the regulations are to be enforced equally, the V-7 should not be allowed. Anyway, v-cubes have tried everything in their power to gain a monopoly, which I think was very unfair.
We made the exception because it was the only 7x7x7 available, but it isn't anymore. Since it isn't, I think that we should enforce the regulations equally and ban it.