It will be more like 500 or 600 lumens if it is driven well. Less than that if not. Don measured a similar light and figured 580 lumens at On, sagging down to 488 after 2 minutes. I wouldn't get an MC-E or P7 light now that XM-L LED's are available. Some of the MC-E and P7 lights have a donut hole of darkness.
Here's my review of a MC-E: https://budgetlightforum.com/t/-/412
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