Just that 😀

RCT3 has 3 position compression adjuster (and threshold adjuster).Dual flow rebound and shim stack (speed sensitive) controlled compression.
RL has a lockout.

The rct3 has three levels of compression damping with a threshold so if you overdamp and then dive into some rough stuff it’ll not knack the fork

The RL has no adjustable compression damping – just a lockout.

Massive difference in compression damper and therefore control / performance. The RL damper is rudimentary at best (non shimmed simple orifice damper). If you plan on hanging onto the fork and you ride hard, get the RCT3 damper and you’ll see what I mean. It is a proper shimmed piston as well as offering low speed compression adjustment. Well worth it.

RCT3 is apparently the better performing of the two. RL locks out & has 5 compression settings from none – lockout.

No more need be said.

Although it probably will 😀

Ah OK. Was looking at blutos which come in both flavours for the same price. RCT3 seems a no brainer then!