Did We Get the Wrong Info on Changing to 600 watts from 1000?

we were told by a grower in berekly that 3 1000 watt lights were overkill, so we switched to 600, our plants are 3 weeks from harvest and look like they just started, the colas are not big at all, should we switch back to the 1000 watts? we did have a spider mite problem in the early stages, and im wondering if that stunted there growth. i took care of them asap, but wonder if we still have some lingerers...but we spraid them with real neem oil, and bomed the room 3 times, with different kind of bombs so they wouldnt get ammune. havent seen any for 4 weeks. our room is 10x10, plenty of ventilation, we got the spiders from the babies we bought, this time we checked them over really well. we kinda waited a little long to flower also they are like 4 feet tall right now...oopsie. we dont usually do that either, this is just a bad round. but a learning one at that. anyone have any good advice?

I personally rock 3600 watts in a 70 square foot space. I have never had a problem with too much light. If anything I would like to add more. However I have heard that 600 watt lights are more energy efficient, meaning they put out more energy per wattage used than do 1ks but 1ks obviously put out more energy overall. That being said, an experienced grower will have great success with 600s or 1000s.

Yes, Spider Mites are the most likely reason that your plants were stunted . I had spider mites on my clones once. I was lucky enough to notice early on and sprayed my clones with an even mix of rubbing alcohol and water. The plants were fine, I did 3 treatments. I've also read great things about Green Lace Wings which are a biological predator to many pests. I just applied them 2 days ago so I couldn't vouch for them quite yet though but I'm pretty confident they will keep my garden pest free. I try to stay away from yucky chemicals.
Good luck