I guess the interest in either Apolo or 161 iare very different depending on your usage requirements. I'm purely recreational these days, but still want speed over handling to a certain degree.
So for me I like the idea of a dedicated lightwind board which I could use up to a max of 15 knots, but ideally gets used in 5 - 12 knots. In a way both the Serenity and the Apollo are matching boards for me, in that lightwinds where I normally wouldn't go out in become accessable to sail.
The things that put me off Formula gear was price and the size of it all and the hideous look of it all! (no offence Tiesda
) I prefered to slog it on my IMCO until one day my buddy who used to bug me to join him in recreational formula sailing went sailing past me in winds I though impossible to plane!
So now I've sort of joined the club with a 10m sail and F-148. I'm just adjusting to the setup and it's funny how you get used to such a big sail!