I have a photonis echo with 2000+ FOM and it’s great when there is some ambient light or with illumination. Haven’t compared it side by side with gen 3 tubes but I don’t think there is much difference those environments. On an overcast night or under canopy with minimal ambient light, the echo tubes will be significantly darker then gen 3 and especially filmless. Nitewalker on YouTube has a pretty good video showing performance in different scenarios. If you’re going to be using IR illumination, I’d probably save the money and go with the echos. If you need low light performance, go with L3.