I believe JackD201 may have a version of CS under his CH gear. I’m not absolutely sure about this so I suggest looking him up and asking him his experience directly. Jack’s system is pictured on the home page of this website. Please note that Jack is a Distributor for CMS products.
Of greater note is the difference between SM and CS2. These 2 products have absolutely nothing in common. There is nothing common about the materials, the approach, the execution of the designs or the intended effect of the products. It is best to think of CS2 as totally different than SM and forget your previous experience. Your experience with CS2 will be different.
In certain ways, the execution of the CH chassis bears similarity to the execution of the advanced Esoteric product’s chassis. Both manufacturers use steel bottom plates with internal isolation schemes designed to lessen the effects of vibration. CS2 works with both manufacturers because they executed their processes without knocking their chassis out of neutral. The settling process may be a bit longer than normal, but this is a temporary condition.
I suggest CS2 0.8 under the X1 and CS2 1.5 under the M1, if budget allows.
I pulled all the built in rods out of my full CH system. I use 1.0s for all except the M1s which use CS2. They are all on CMS Maxxum Filters.
Before the CS feet I preferred the CH sound with the feet flat on the CMS interface discs. In general I do not like spikes unless they are used in conjuction or within a system. I find that with the exception of very heavy speakers, there is a pronounced thinning of the sound. A "tipping up" if you will.
As Joe said The CS share the same DNA as the filters. So, the immersive effect wasn't a shock to me, it just enhanced it the same way one would if goinng from Sapphire to Black Platinum to BBlack Diamond to Maxxum. My speakers are also immersive to begin with because of their radiation pattern.
So in my own experience what the CS' added most was refinement of already existing detail. By that I mean better differentiation of timbres. Piccolos vs Flutes, Violins vs Violas en masse so on and so forth. On ordinary recordings the refinement is most appreciated on reverb especially with cymbals which can decay into whitish noise instead of silence.
That said, CH is heroically built and have suspended boards. With my Lamms and KRs which use stamped metal chassis construction the amount of added refinement is more obvious.
As I said in my system page, I don't like footers or platforms that alter the tonality of my electronics. I worked and saved to get the stuff, I want to hear what I paid for. For me the CS' were more evolution rather than revolution. The revolution was CMS vs my own pitiful DIY attempts.
Oh, and by the way, while we are one of the earliest CMS distributors, first outside the USA in fact, we have yet to sign up formally for CS. Because stocking these can eat up capital really quickly, I needed to bring the feet around first for our own more expanded evaluation in systems we didn't commission from the ground up which is what we mostly do. I can say that their effect is pretty much universal. As such, we will be signing up probably by the beginning of the second quarter after we have restocked our thinning speaker, TT and cable inventories.