I don't know about "best" since I haven't used them all side-by-side, but I really like my Fluval Plant 3.0.

On my 75 gallon (low-medium-ish light), I never have it past 50% brightness at any point in the day, so it's quite powerful for it's size.

My favorite part is just how customizable the programing is. You can set each of the 5 colors in 1% increments. And also set each color on it's own schedule with I think up to 8 different time points... So I have a specific sunrise, morning, mid-day, evening, sunset, moonlight, and night phases that all transition smoothly from one to the next that I just enjoy the look of. And my mid-day is what's programed specifically for the plants, that seem to love this thing... Or just a couple time points could still be used to set simple on/off times if you didn't wanna screw with the rest of it.

Biggest complaint with it is really the option paralysis and learning curve.... Not with setting the light since the app is actually pretty self explanatory, but figuring out what settings to use. There's a lot of trial and error while getting it dialed in.