I had a chat with CG last week regarding tyres, as I'm thinking of moving to Cup2s (which apparently isn't really doable unless you're running a minimum of 2deg neg camber all round, as it requires a certain contact patch to achieve the correct grip levels. Anything under that and you'll simply wear the tyre too quickly in the wrong places) and I asked them their opinions on the regular MPS4. The consensus was that they're significantly better than the MPSS, mostly due to using the same 4-compound construction as the Cup2s rather than the 2-compound construction in the MPSS.
I mention this as the guy in the link says that he couldn't tell the difference between MPSS and MPS4S, which kinda contradicts that. Michelins are also quite noisy road tyres (their one big downfall), so it's surprising to hear him say that he found road noise minimal on the 4S. That said, road noise is subjective.
That's not to knock the quality of the review at all, and indeed he clearly knows his stuff, just quirks of different opinions is all. Interesting how he says that 18" and 17" are coming in 2018, which I find to be both very good news and also very surprising. Personally I'll be amazed if they do, but it certainly makes tyre choice for next year interesting. For now, I'm keen to try the MPS4 and see what they're like.