I don't quite understand the need for a lengthy discussion when obviously the translated spec sheet shows the pandaminer mines 230 MH/s while consuming 1600w whereas the E3 does 180 MH/s at only 800w. Thats like comparing pandaminer's 7 watts per 1 MH to bitmain's 4.5watts per 1 MH.
Seems pretty clear that the E3 is much more efficient and profitable option. I hope pandaminer gave that to you to review for free.
pandaminer 1600W is just PSU spec not the consumption. Consumption should be around 1050W.
B3 is 1250w on eth, if the b3 was 180mh like the e3, it would be a little over 1000w. Makes the e3 about 200w more efficient at the same hashrate.