I just finished my first roll of Canson Baryta Photographique on a P800. I had no problems till the roll was almost at an end, when I got head strikes. I also noted that the last 5 feet of the roll had indentations from where the end was glued to the core. So it is not really a 50 foot roll, but actually ~45 usable feet.
This decurling technique may mitigate the headstrike issues I saw. I presume it was because the curl problem is greater towards the end of the roll. I just loaded a new roll of the same paper, and no problems.