I had it from previous giveaway but it expired. Yes, it was good. But then I looked for a replacement and came around f.lux (yes, the name is “f.lux”).
It’s free (donationware) and I guess it’s much better: much more options to tweak it to your taste. It even works with some smart Philips bulbs but this part is beyond me:). All in all, once I tried it I never looked back.