Hey Cal, so your going from a plastic grover to down river rollerblading. You know what they say about fat chicks and scooters... Whats the hardest thing about rollerblading...
Jenny has the Sevlor Somoa inflatable and a "soft top" deck at Ragged. Not what your looking for. The Hala seemed like a good option. For my $$ I'd support Mike Harvey and the guys at Bad Fish. The board(s) are great on the river and lakes. Super stable, a bit slower on the flat water, but your not on a sup downriver for speed. Did not notice the slight amount of water on the deck. For ocean, the bad fish would be OK in the swells, but not a hard enough chine to really surf a wave. That is what glassed foam is for. Man is it hard catching waves in the ocean.
I Have not had a chance to try them, but my brother has a Hobie "School" that he thinks is great. He also has a quiver of Riviera and Hobie glass boards.
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