Hey luciferi, I don't know who's LED panels you have but you'd be better off growing smaller plants just because most budget LED panels only have an effective growth area of anywhere from 1 1/2 to 3 feet high depending on the quality of LEDs used and a few other variables. From what I've seen once you get past a certain height a LED grown MMJ plant will just lollipop itself from light starvation. Best to grow smaller plants with an even canopy, but it might be possible to do 2 larger ones with the 450w as the main panel and the 300w a side lighting. Still "450w" and "300w" need to be using some decent quality LEDs with tight beam angles to be effective when growing taller plants. Some smart training on a smaller size plant can yield some decent numbers and most LEDs out there really do better with smaller plants so if you want my opinion from a LED grower's perspective, do the smaller plants. Good Luck!
