I have both and I prefer my ss, my times dropped like 2-3 minutes in 3 solves after I got it
take the entire cube apart including the core and apply lube there.
If you can manage you can take only the yellow side off up to halfway and then just lube the yellow core centerpiece bit.
It all depend for me. I'm not a competitor, only a hobby. However the shengshou is much smoother, almost unreal in smoothness, requires no breaking in. But, it's not quite comfortable yet, my V-cube finally met it's demise, but after its break in phase, it was phenom even without any lube. I'm curious to how the SS holds up after quite a few solves. overall, I voted v-cube, only because I had some really good ones.
I would definitely say SS, V7 is rough while SS is smooth and easy to turn from the beginning.
I voted V-cube because Ive got two sets of 5-7 and ive never tried the SS