Dyn8

Inserting a Dyn8 adds 4 samples on input / bus processing (42us).

RackExtra FX

Inserting a De-esser, Transient Controller, DynEQ or Doubler from the FX Rack adds 27 samples on input / bus processing (281us).

RackUltra FX latency

All RackUltra effects incur a transport latency of 0.1875ms.

In addition:
Plate Reverb and Spaces have zero processing latency.
Amb+Cab distortion and Saturator have 0.0104ms of processing latency, but the wet/dry path when inserted is compensated to avoid any phasing issue.

With Harmonisers, Tuner, Gridder and Shifter, the processing latency varies (this is common across tuning/shifting FX or plugins). Some of these FX are using the ARM core which also adds a block latency of around 10ms.

Total latency for Vocal Shifter and Harmonisers is 16-26ms (block + processing + transport).
Total latency for Vocal Gridder is 21-32ms. 
Total latency for Vocal Tuner is 6-11ms.