The vero is a good chip you just get more ppfd with the citizen or luminus with the same amount of cobs you also can run the citizen harder if you wanted.
Using the led calculator
VERO29.V2.0.4000K 9 COBS @2.1A ON 1.813 PROFILE HEATSINK
16 SQ.FT. CANOPY 93% EFFICIENT DRIVER @10 CENTS PER KWH
Total power watts at the wall: 772.04
Cobs power watts: 718
Total voltage forward: 342
Total lumens: 94848
Total PAR watts assuming 10% loss: 263
Total PPF: 1215.06
PPFD based on canopy area: 817.42
Citizen.1818C4.3000K 9 COBS @2.1A ON 1.813 PROFILE HEATSINK
16 SQ.FT. CANOPY 93% EFFICIENT DRIVER @10 CENTS PER KWH
Total power watts at the wall: 1097.85
Cobs power watts: 1021
Total voltage forward: 486
Total lumens: 140898
Total PAR watts assuming 10% loss: 387
Total PPF: 1880.82
PPFD based on canopy area: 1265.31
Curious....How come I'm getting such low efficiency numbers on the citi's compared to the cree at the higher wattage...
CXB3590CD36V3500K 9 COBS @1.75A ON 1.813 PROFILE HEATSINK
16 SQ.FT. CANOPY 94% EFFICIENT DRIVER @8.5 CENTS PER KWH
Total power watts at the wall: 594.68
Cobs power watts: 559
Total voltage forward: 319
Total lumens: 91452
Total PAR watts assuming 10% loss: 266
Total PPF: 1236.9
PPFD based on canopy area: 832.12
PAR watts per sq.ft.: 16.63
Cob efficiency: 52.87%
Power watts per sq.ft.: 34.94
Voltage forward per cob: 35.49
Lumens per watt: 163.6
1212 3500K80Min 9 COBS @1675 mA ON 1.813 PROFILE HEATSINK
16 SQ.FT. CANOPY 94% EFFICIENT DRIVER @8.5 CENTS PER KWH
Total power watts at the wall: 601.18
Cobs power watts: 565.11
Total voltage forward: 337.38
Total lumens: 82989.60
Total PAR watts assuming 10% loss: 222.96
Total PPF: 1191.58
PPFD based on canopy area: 801.63
PAR watts per sq.ft.: 13.93
Cob efficiency: 43.84%
Power watts per sq.ft.: 35.32
Voltage forward per cob: 37.49
Lumens per watt: 146.86
1818 3500K80Min 9 COBS
@1200 mA ON 1.813 PROFILE HEATSINK
16 SQ.FT. CANOPY 94% EFFICIENT DRIVER @8.5 CENTS PER KWH
Total power watts at the wall: 600.84
Cobs power watts: 564.79
Total voltage forward: 470.66
Total lumens: 90389.25
Total PAR watts assuming 10% loss: 242.84
Total PPF: 1297.83
PPFD based on canopy area: 873.11
PAR watts per sq.ft.: 15.18
Cob efficiency: 47.77%
Power watts per sq.ft.: 35.30
Voltage forward per cob: 52.30
Lumens per watt: 160.04
So it seems to me, best bet to stick with the 3590's (efficiency) if I plan on running them at a combined total wall draw of 450w-600w?
Or the 1818 citi's for the discounted price?