LifeReef
 

LifeReef overflow boxes are one of the best as they do not require the lifters and pumps a CPR one requires so the siphon does not get broken. I have never had the siphon break on the LifeReef after a power outage or pump restart. There have been times though where the overflow could not keep up initially when the pump restarted and therefore the water in the tank was very high, near overflowing.

One other drawback of a HOB overflow is they don't seem to have the same flow capability a drilled tank would have. Finally, I am not a fan of the look, as there is a big box in your tank, which I find more obvious than the corner overflows.

A drilled tank is a better option, but a HOB overflow can work.
I have a LifeReef and it is easy, but I can't wait until I have a drilled tank and built in Herbie overflow.