HOB filters are fine, depending on what you are doing.
For example, if you are injecting CO2, you will want to minimize the amount of surface disruption there is, so a HOB filter may not be the best choice (the filter return waterfall creates quite a bit of surface disruption).
In addition, the biowheel adds more surface area, allowing CO2 to off gas faster.
Of course, this is not really a problem if you are not planning to inject CO2.