Hey Zach....here is the facts as I know them.
The core materials used in the Sub 6 / Marek are much lighter PVC Cores and much more difficult to work with to make as they have to be CNC'd one at a time. But when laid up, they will make the board torsionally stiffer (twisting flex) which translates to more speed to the wake. This also allows them to still have "flex" tip to tail" on boards. Ronix Dark Core is similar materials and give the same enhanced performance and acceleration. Their R & D team that has ridden the boards also has said they are extremely durable also. Slingshot uses this same material combined with wood in their cores, and I'm pretty confident Company will also. As for LF...They are saying they are using the PVC core in them with a multilayered stringer system and 2 pack inserts to cut down on the weight.
So back to your original question...SPEED to the wake and away from the wake....enhanced energy off the wake from faster rebound characteristic of the core and enhanced durability (from what I hear).
As for the pros riding them / not riding them. The reality here is, that even for athletes getting "flowed product"...flowing these more expensive boards to get beat up on rails is hard on the wallet. You will see alot of pro's freeriding with these...but on rails...boards still get broken and it hits the wallets of comapanies hard...so look for more standard core boards on rails. Thats my take as I know it.
Good luck with your search...if you get to Orlando and want to demo some...we currently have Mareks, Slingshot, and hope to have others in the coming season.
Bill @ Performance. www.perfski.com
(Message edited by perfski on November 07, 2008)