Put the Lyndalls the '08 SE road king that I had. They squealed bad. Called Lyndall and had some more sent out with a compound that "would not squeal". They squealed too! Lyndall sent out some goop to coat the back side of the pads.....you guessed...they still squealed.....and so did the BSR! Less "bite" too. They had good customer service but....
No more Lyndalls for me. Might try the EBC this time on the street glide.
Sounds like you may have had something else going on besides just the pads. If I remember correctly Harley had the same problem with the stock pads on the rear on the '08 models.
Next time you change pads make absolutely certain the rotors are free of contamination and also check the pistons in the calipers for even movement. Lyndall has a bulletin on their site with a recommended routine for cleaning and inspecting the caliper pistons btw, and it works well.
I've had great service from the Z+ pads, with a better braking "feel" and much less dust than other traditional pads (haven't tried ceramic, don't see the need). As you go from the Z+ to the Gold pads, you get a little more bite but the tradeoff is a bit more noise as well.
Jerry