Ran it twice this year, once at 800 at put in and once at 550. 500 is probably the lowest I would run it, the meat of the run would still be good fun at lower levels, but the paddle in and out would be long and bony. Especially the paddle out, it would be brutal and you would need so much booze you probably wouldn't be able to drive home and would have to camp at the mosquito infested takeout and suffer from west nile for the rest of the summer - not really worth it.
If you do go post so we know what it is really like at that level.
Whiskey's for drinkin' and waters for fightin'
- Mark Twain