decision is up to you and your situation. I added a WavySea+ to my running 90 but if I were to do it again, and I was starting a new tank, I would go OM 4 way and drill holes on the back of tank at different levels so I would have no powerheads in the display at all. looks like that would be great even in a closed loop system.....like anything else, its a toy. Not needed to be successful but sure nice to have if you can afford it.
I agree, although after poweroutage, the wavysea needing to be reset is easy, sometimes can be annoying....you can attach the wavysea to an UPS but that adds expense.....again, if I were to have done it over, would have gotten an OM
Do not know the reliability of OM but just like the rest, they are not water-proof......wish someone would design a product for a change that was....wonder how hot a OM gets, could you encase it in a balloon like the old analog speed controller on an RC car....