-- Last Updated: Mar-09-12 8:22 AM EST --
We usually paddle 9-10 miles at a stretch, but that's because we have driving time, shuttle, and I take a lot of pictures and occasionally fish. Also that's about the length my wife likes. If you like to fish, that or a few less miles. If you're the kind of person that is interested in getting from point A to point B, don't believe in taking breaks, pictures, and enjoying the scenery, 25 miles a day is easily done. Also if water levels are up, it will go much further.
If the water level is at least 350cfs on the Montauk gauge, I'd start at Baptist Camp access. If less, probably Cedar Grove. If in drought, you may have to start at Akers. By then, there's always plenty of water as Welch Spring dumps in about 1.5 miles above. Heck, there's actually a small access right there that you can put in at.
We typically don't paddle much below Powder Mill Ferry/Owl's Bend. You start seeing jet boats about Round Spring and the further down you go, the more frequently you'll see them. Even through the week, you'll see them in July and August. Personally, I probably would go no further than Big Spring (a few miles below Van Buren). That's going to be about 80-90 miles and 4-5 days.
I've been paddling there since the '70's, but my buddy Bob has been paddling there even more. He also recently did a trip down to Doniphan (a little above the Arkansas line). I'll clue him in and he'll give you some invaluable information.