It would be great to have some travel adjust (i.e. duel position) for climbing although from what I can make out none of these have that function – not essential but nice to have.
They will if they’re called “Dual-Position”. That’s the spring, the RL, RLT, etc is the damper.
RL= Rebound and lockout (really a low-speed compression) adjustment.
RLT= rebound, ‘lockout’ and threshold (opens up the damper on big hits if the low-speed comp is closed).
RCT3= Rebound, compression and threshold (3-positions, kind of like Fox’s CTD stuff, a platform damper with open, middle and closed settings)
Personally I prefer at least an RLT damper as it allows you to dial in some low-speed comp. whilst using the threshold to keep it open for the bigger stuff.