I’we done some measurements too and my results are a bit different.
From analog input to analog output, using no blocks, I measure 1.86 ms of latency no matter how many rows I’m using. This is with firmware 2.0.0. With firmware 1.4 I did see and increase in latency (approx. 1.8 ms) when adding row 3/4 to row 1/2.
Using a send+return adds another 1.86 ms of latency.
An amp capture together with a cab block adds approximately 1 ms.
Most of the effects adds latency and with my most “crowded” presets I end up with around 8 ms of total latency.