Get a LSV for WPA usage. The nanos great but I personally find logs a little anemic in use through glass, that's probably due to the log running at ~15 peak watts and the LSV running around 35.
The LSV heats up faster, provides bigger hits, and is more versatile due to the 18mm glass fitting. With arizer basket screens I'd say efficiency is certainly on par with nano, the only caveat is its somewhat long and ungainly. Just my .02, my LSV is in constant rotation.
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