My experience has been that
Sabian is trying to be on the cutting edge of new sounds and ideas, and
Zildjian, although once an innovator and producer of the newest latest sound is playing it more conservative and sticking to more traditional sounds. Although I love some of the sound and feel of
Zildjian cymbals (especially the K's), I am also looking harder at
Sabian's HHX and AAX lines to develop my modern sound.
There has been a recent exodus of sorts by some of the biggest names in music from
Zildjian to
Sabian endorsement. Although, as Damo has pointed out in another thread, endorsers are looking for exposure and what the company can do for them in terms of gear etc., I think
Sabian's willingness to develop lines of cymbals around a persona and their sound/technique (big names obviously) has lead to more of them coming over.
Think of Neil Peart, and Dave Weckl for example. Both avid endorsers of
Zildjian not too long ago, now each have their own lines of cymbals with
Sabian. Neil Peart has the Paragon series, and Dave Weckl has the Evolution series.
So although I love the K's and the way they feel and sound, I am gonna have to say
Sabian is moving in a more modern direction with prototypes and innovation--not that
Zildjian can't do that as well, but they just aren't to the level that
Sabian is...