They're probably too new but has anybody played the new K customs? There's a high definition ride, a left side ride, and fast crashes. I'm interested in these cymbals myself. (There are also new effects and Z customs and sticks but nothing as interesting as these) Also pearl has introduced the MSX which is a covered masters series, so perfect for touring.

I tried the K Custom Fast Crashes, and they're pretty cool.  similar to the A Custom Fast Crashes with the quick attack and decay.  also, like the ACFC's, they seem quieter than their regular K Custom counterparts.  tonally, they've got a more low middy sound to them, while the ACFC's shimmer and sizzly up top.  i kinda prefer the ACFC's.

they call the Left Side Ride that cause its supposed to be the auxillary ride on a jazzer's left side.  to me, it seems nothing more than a K Custom Dry ride with 3 little rivets grouped on one side.   tonally, it sounds just like the way i described.  its an ok jazzy cymbal that gives a mild attack, dry "ding", and pleasant overall sizzle with a nice amount of wash.  but, just the fact they call it a "Left Side" ride makes it kinda lame to me.  

didnt have too much time with the High Def, but it seemed like another K Custom Dy variant.  muted ping with little overtones and whatnot.

In 2003 Zildjian, in collaboration with Peter (Erskine), introduced the K Custom Left Side Ride. Conceived to be the Jazz Drummer's all-important "2nd" Ride, Peter explained how the idea for the Left Side Ride came about:

"I asked Zildjian to create a cymbal that could compliment my Ride and Crash choices, a cymbal that would add a new dimension to my music, with warmth, clarity and variety but still with a unique sound: in short, a cymbal that could be my main Ride cymbal's "best friend"; and this is how the Left Side Ride was born"

Peter Erskine uses a Constantinople medium ride.