They both cooked for total of 17 hours. I had probes in both but one of them appeared to be not working. Anyhow, they came out OK, but the ragged end had much more bark to it than the good end.
Erego, I'll probably try string if the need arises again, as I would rather have tender meat than chewy bark for sammijes. For those looking for more bark, cutting up the ends to expose more surface will do the trick.