Based on my discussion with geo installers, as well as this community, it seems that there is a general consensus that stage 2 heat is "bad." I believe this is because the COP number is worse in stage 2 than it is in stage 1, giving people the impression that it is a less efficient heating stage. I had one installer I talked to actually size the unit to avoid all stage 2 operation, he was all about the higher stage 1 COP number. There are posts on this forum about folks trying to keep their thermostats from entering stage 2 as well. However, if the energy monitoring on my WF 5 Series is correct, I would have to say that stage 2 is actually better than stage 1 in terms of efficiency. Let me give an example: Stage 1 on WF 4-ton: Fan: 39w Pumps: 472w Compressor: ~1739w (varies up and down continuously) Total: ~2250w Stage 2 on WF 4-ton: Fan: 39w Pumps: 472w Compressor: ~1939w (varies up and down continuously) Total: ~2450w So it seems stage 2 consumes about 200w more than stage 1. This is a difference of about 9% total wattage. Given that stage 2 actually produces about 30% more heat than stage 1, isn't stage 2 actually more efficient when the overall operation of the furnace (pumps and fan in addition to compressor) is considered? This all of course assumes my energy reporting is accurate.