Kessils are amazing. Where else can you find 30w of light that will produce decent buds? You can grow better with two, but if space is tight, a single Kessil will do the job.
I have a magenta, and I'm thinking of getting a purple. When I corresponded with Kessil, they said their new white light wasn't testing as well as they'd hoped. Maybe they sorted it out?
Grener's has a good price.