YES. Now is the time.
Its incredibly undervalued - the S glass typically retailed in the range of 5-9k and the reason it is depressed, besides being mirror based, is because literally the only mount available are S bodies.
This is all set to change with the S4 which will be able via adapters use:
M
SL
S vintage glass
If you buy S glass, all lenses are great to be honest. I cannot fault a single optic.
The S24, S100 command a heavy premium because they were produced later and are rare. If you can get these in mint condition, IMHO, any price below retail is amazing.
I hear that M glass will be even adaptable via an AF adapter ... how amazing is this?
Latest update I have on the next-gen S glass is that it'll be 2.5 AF APO, couldn't validate CS, but I think they are.
The dream kit for me personally therefore is:
M12M
S4
Alpa with P1 backs
Arca R+F for film
The S4 covers colour Leica, the M12M will be a 100 MPX B&W camera so both systems are complementary in terms of capabilities.
For the hardcore IQ and res you pull up P1 with tech cam. Arca is unmatched for hybrid, IMHO, especially due to the interchangeability between bellows and pancake cams + the rotaslide.