Echo tube is like a run of the mill thin filmed for light amplification and resolution where the L3 unfilmed is noticeably better in low light amplification and probably better resolution too. The Echo is better in light polluted environments because it does not really loose resolution in bright conditions, where the L3 is really going to loose detail with too much light. The time you want an Echo tube would be if you drive in a car with dash lights or are in an urban or suburban type area with lots if light pollution. The L3 unfilmed is better for rural, dark nights, under forrest canopy, etc. The Echo is actually not the top tier Photonis tube either, its a second tier tube. Their 4G Intens tubes are the top tier tubes. The L3 2200 tubes are the best L3 tubes you can get at the moment. So what is most important to you? Dealing with very low light, or dealing with very high light environments? The Echo tube is much more resistant to recoil but that is not an issue for goggles. And if you can afford a REAP IR and MAWL it does not sound like you really have any budget limitations other than ones you arbitrarily set. Photonis tubes tend to be more expensive.