Although i have probably stated this over 100 times let me explain the difference between the carpet knife and rev. 3. the rev. 3 has the old style front end which works better on carpet and is much more consistant. It also has a much better roll center, the CRC's is way to high and you need to get the speedmerchant style side links (which are also much better, since they are adjustable, dont readjust in a hit, and are much more precise), and also the knife has too much machining in the back part of the chassis so it flexes exactly where it shouldnt.
the crc 6 uses damper tubes just like the rev. 3 and carper knife, but has a t-bar (the l3 uses disks, however in the picture of that car it showed it had damper tubes, which you can convert to, however its a pain, and yes tubes are much better than disks).