Honestly if you know how to surf and just want a cheap summer ride, that should shred. I like twin fins. Super fun, super slidey and pivoty. A 54" board, aka 4'6" is quite short though. Unless you're looking for a 5'4"? I see they have a 54" beater board, which I'm assuming is what you mean. Plenty of good people ride them in the summer, or to be funny in good waves. I've only ever seen kids on the 54" board though, the single fin one.
Longboards are fun and catch everything, and noseriding is super cool. But if you want to shortboard you'll end up selling it, unless you want to build a quiver.
Short, stubby, flat rockered boards are good if you know how to actually catch a wave and, well, surf. You can learn on one of course, but it will require more fitness and better waves. They don't ride 2" lumps like a longboard.
High performance shortboards are sort of silly in the summer (in jersey anyway), unless there's actually good waves. A small wave shortboard is a much better bet. Fine in the winter, of course.
If you can't reliably get into waves and get up and surfing, then maybe 4'6" would be very short for you, or if you're like six feet tall or something. If you want to build a quiver and surf more, and surf the summer only, might as well grab a longboard or small wave shortboard. I have a 5'4"x20.75x2.25 small wave stubby thing, a 5'5"x19"x2.25 good wave shortboard and a 6'4"x22" single fin that floats me so well I compete with longboarders for waves. I have a thread on the first two, I shaped them. I've never surfed a 4'6", but I'd imagine it would be quite fun once you got up and riding, especially as a twin. Those things are buoyant too.
What is your previous experience on/can you reliably get into a wave, get to your feet and surf?
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