I personally would not use it.
Could be a pain to get to to clean, and you would want to REGULARLY clean anything with carbon and floss in it. If you have LR, I wouldn't see the point.
Plus it probably takes up space...its not a big tank overall. Space is precious. I would put a piece of LR in that space if I had to make a choice.
I would use the powerhead, but not the filter. Now if you have no LR and no other filtration, that may be a different issue.