I put an ARF bracelet on my VSF 124060 just today. It is different, I'd say overall better, than the VSF bracelet, but it's not night and day. I had expected more, and I'd say it's not really worth the money, considering that we are talking about reps (I paid 140 Euro incl. shipping for the bracelet, but I believe there are vendors that even charge over 200 USD).
The main difference is, that the gaps between the links are tighter on the ARF, which should be a bit more gen-like. It is probably not something you can see when the watch is on your wrist, but you can see it side by side. The ARF is hence slightly shorter than the VSF, I'd say somewhere between 1 and 2mm.
The external finishing is very similar, also SEL fit is very similar. On the VSF I found metal shavings in all drillholes when I sized the bracelet - this was not the case on the ARF, the finishing of these fine details is better.
The fold-over security lock closes tighter on the ARF, which I prefer, not sure though how the gen would feel.
The engravings on the ARF (clasp and SEL) are deeper, which looks better, but the "Rolex" engraving feels a bit sharp-edged.
The VSF bracelet was quite squeaky when it was new. This has improved a bit over the past two months, and the new ARF sounds like the used VSF does (which is better than the VSF when it was new).
So it really is just a marginal improvement overall. The bracelet on my CF 126500 remains the best rep bracelet in my collection by far. I was hoping that the ARF bracelet for the Sub would give a similarly premium impression, but it does not.
As I said in the beginning - it's not worth the money to swap the VSF bracelet for an ARF one. The differences are really just small details that don't have much of an impact when wearing the watch.