Don't spend money twice. If you go kessil, you'll need some back up light. It's a beautiful effect but having more than you need is always better imho. Also, if you ever do go hybrid, which you don't need to necessarily with the hydras, you can do that with an easier form factor, oh and no added controller needed. It's a scam I tell ya. If you want to see what hydras do on their own, go check out Junio Melo's TOTM. I use Hydra 52 HDs too so I'm biased but practical.