Rega RB600 vs SME M2 vs Clearaudio Satisfy Satine

Hello all, my first thread starter here.

My Rega is upgraded with Incognito wiring, HeavyWeight and VPI VTA (SRA) adjuster. Sounds really good, but I think I should at least try to get a bit more control in the bass region, especially very low bass. Also, soundstage is somewhat undefined (more on some records, less on the other - and no, I will not adjust SRA for every record), and complete picture is missing a bit in the high region ("air"). All of those reasons might be just my skewed perception, due to the upgraditis.

My system is:
Sota Sapphire w. Goldmund Relief Mat
Rega RB600
Sumiko Blackbird
Cary 300SEI
Reference 3A Veena
IsoTek Multiway 6
All cables are Refence 3A

My vinyl collection spans from Bach to Khachaturian, ACDC to ZZ Top, Louis Armstrong to Nina Simone, JJ Cale to Ry Cooder but I spend most of my time in the region between Jethro Tull and Pink Floyd.

I am using solid rosewood armboard with Rega right now, and will switch to the solid mahogany with the new arm. There was audible improvement going from MDF to rosewood, and blank mahogany AB is already at home.
I really like the sound of Sumiko Blackbird, it makes love to ARC. Later on, I might get Benz Wood H2 or something like that.

I am considering brand new SME M2 and mint used Clearaudio Satisfy Satine.

SME M2 comes with its own cable, Clearaudio comes with the captive (factory) wires.
SME looks like work of a watchmaker, Clearaudio looks like a patient work of an artist.
SME has a good reputation on the suspended tables, I don't know anything about Clearaudio.
Brand new SME is almost $400 more. But, it is brand new.
Also, with SME I could go with M2-10, which would give me the additional 6.1 mm of effective length - which would bring (actually negligent... but its there) improvement on the tangential error.

Did anyone compare the two (well, three)?
What should jive better with Sapphire and Blackbird?
Would any of those two arms present a tangible upgrade, or would it be "just a different flavor"?

Thank you!