I just discussed this question while ordering my new set of sails from Randy Smyth. Randy sez...
1. Harken's "rolling Battens" are okay for a fully battened jib, but with those short 10 inch battens, the roll-able ones don't smoothely roll up, stick out and generally act uncivilized when you furl.
2. He recommended the parallel-to-the-luff aproach, not mentioning a hollow leach. This was for a new sail, perhaps his advice would have been different for an existing sail. I'm going that route.
I can't wait for my new sails.