We have used both Parrel beads and the ATN Tacker. Both work but the Tacker is somewhat better at passing over the furled headsail (a good coating of SailKote helps). On that subject, we do not allow the sheets from the jib to coil down and around the furled sail so that the tacker must slide over them but keep them tight between the sail and the sheet leads. The tightened jib sheets act as preventers to disallow the spinnakers to wrap inside the furled jib and the mast; and, as a positive "stop" to limit the Tacker's vertical range of motion, in our case about 12-14 feet above the stemhead.
With both the symmetric and asymmetric, the tack line passes through a snatch-block at the bow roller and can be adjusted up-or down quite easily using a cabin-top winch. The tacker is really unnecessary for the asymmetric but quite useful for the symmetric (in our case 1500+ sf) which we can carry from about 60º to 140º apparent with apparent winds up to about 12-15 knts. With both sails we use "inside gybes" with the lazy sheets passing forward of the headstay but aft of the tack/luff of the sail, which keeps things under control as one gybes and the lazy sheet out from under the boat.
FWIW...