I also had two full grows with the Mars II 700 and they did my Space Jill the way my newer panels did, but with more heat, noise, power consumption and less penetration. I never did a side by side with Black Dog but would be hard pressed to believe the diff would be justified on day to day performance alone. We don't work hard at this with a day to day strategy, so Mars II and other similar cheap lights are not worth it. Its the reliability issue I am concerned with, that and all the issues when the problems do arise. Performance is the same like I said, but for how long? I just didn't want the anxiety. People don't want to hear it but the safety, turnaround time for any repairs, talking easily and with good response time to a US based company - all these things make the few extra duckies worth it.