I have had single sealed, doubles and triples. Cost and room the double is best bang for buck. If you can afford triples, do it, as you can always reduce output to match your speakers. Single is not going to get you where you want to go is my guess. You can face the either way, same or inverted, just wire them correctly since the phase will be swapped on the drivers that are reverse. I would have to defer to someone higher up, but the only reason for inversion would be weight distribution or ease of panel design. I have seen both, no issues either way. Good Luck.