If you are planning to do any racing on this new board, I would DEFINITELY go for the HWR. Without going in too much details, the HWR simply has better angle/speed upwind and downwind due to it's wider tail.
However if you were planning on using the board for lightwind cruising or just for fun sailing, then you could go for the LWR as it has a smaller tail and is a bit more comfortable to ride in chop and through the gybes...
Most likely you'll have better resale of the HWR down the track as it's still a top race board competitive with the newest shapes.
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