Hello, My name is Jeffrey, im from Holland, and i want to build my first led grow light. i have a 4x4 grow tent. I am on a tight budget so i am interested in the cxa2530 and cxa2540. The 2530 i can buy for 6 usd/piece and the 2540 for 10 usd/piece. The 2530 has a max of 1600ma and the 2540 a max of 2100 ma. If both would run at 1050ma, would they be identical, or would the cxa2540 give more light? I Also wonder whats like the sweet spot to feed these cobs, is 1050ma alright or is it quite high? Im not going for highest efficiency but most light for the money, but i think 1400ma wouldnt be an option since they would run very very inefficient? I want to make 3 2 foot bars with 4x2530 or 4x2540, so total of 12 cobs with 3 of this drivers: meanwell led psu-HLG-185-C1050A So im really wondering if the 2540's are worth the 10 usd compared to the 6 usd for the 2530's, and will the 2540 give more light then the 2530 if both run at 1050ma? The specsheets dont tell much, 4545 lux for the 2540 CRI80 at 1100ma vs 3440 lux for the 2530 CRI80 at 800 ma, so would the 2530 also give 4545 lux at 1100ma? I know its a lot of questions but maybe theres people here that had experience with 2540's. Edit: i made a mistake about the lux specs from the data sheet, i thought both were mesured at 1100 ma but the 2530 is mesured at 800ma in the data sheet. Also in the datasheet, it says cxa2530 800ma 36.4v, cxa 2540 1100ma 36.2v. So the 2540 runs a lower voltage at a higher amp, what does this tell? edit: Now i also found cxa2520 for 4 usd/piece, its max power is 47 watts, vs 65 watts for the 2530 and 86 watts for the 2540. So if one would want to run 18 cobs at 700ma ( 25 watts) Would the cxa 2520 be the best then it being 50% cheaper then the 2530, the 2540 costs 2.5 times more then the 2520. would the 2530 or 2540 run more efficient at 700 ma ( 25 watts) ? Or is the only difference the cxa2520 can run at max 1250ma and the cxa2530 max 1600ma and the 2540 max 2100ma. links to the specs of all 3 chips: XLamp CXA2520 XLamp CXA2530 http://www.cree.com/led-components/products/xlamp-leds-integrated-arrays/xlamp-cxa2540 the 2520 has 155 lm/W, and the 2530 145 lm/W but is that tested at the same amp,or is the 2520 tested at 550ma and would it also have 145lm/W at 800ma?