Jm. said:
Because internally they are extremely different, the "HSCV" is just a name, not a super-accurate description of how it works. The 888 has low and high speed compression damping, it is not an 8" "super-t" style cartridge. The older "HSCV" cartridges are most definitely different. Despite the internal differences, there's also other differences that are an elementry change from how marzocchis are put together, the jam-nuts, the simplified preload, etc...
The boxxers on the other hand...well I've taken them apart, and yes they are 98% the same.
I've had a 1999 and a 2003, as well as I have worked on and opened up others. I also had a "compression cartridge" in my 2003 race, so it was essentiall a world cup.
It doesn't matter what I think, the damping technology they use is outdated and innefficiant. Sure, with enough engineering it can be made to work "ok", but rockshox is continually trying to create the ultimate "drum brake", when it is proven that disc brakes are far superior. Sure you can make it work, but it's a waste of resources and it is definitely debatable whether you'll ever be able to get "equal" performance. A wise person in the industry once said that when you are trying to design a fork with that kind of damping system, it's like trying to do it with one hand tied behind your back. BTW, all the other fork makers have systems that use shims, do you think they MIGHT be onto something? Or is RS really that good? lol...