I bought Camera.net last year for 1.3% of the last .com sale for the same word ($1.5m).
...Don't know what that says about .net values, but I had an offer for it recently for $100...LOl
In general, I'd say about 10%, as a rule of thumb....tho, the true premiums can be anything, depending on market niche, end user need, commercial potential etc etc - as they can be for the true premium .com's.
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