Why are you getting an F500 for Freeriding? That frame is designed for a lightweight XC style of riding. For the same money and even less, you can get a FR specific hardtail that'll outlast the F500 for years. I'd suggest something like a COVE or a LeToy, or a Planet X or....etc.
The guys at
www.unrealcycles.com are very knowledgable about FR hardtails. I'd suggest asking them about what you're trying to do.
But, back to your original question. I've test ridden the new Sherman on a Cannondale Gemini 900, and it's a solid stiff fork. Very smooth. With that said, I still like a Marzocchi over the Manitou. I'd go with the reducer cups and buy a Z-1 or a Shiver.
L8R
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"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming, "WOW, What a Ride!" - unknown
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