Another vote for the later ("leakproof") seals.
Originally posted by SBoyd:
Leak Proofs seem to have more stiction and don't work any better.
Fwiw, I never noticed any more stiction on the T160's forks when I swapped 'em to Leakproofs, but the Progressive Suspension replacement for the damper top 'O'-ring does reduce stiction.
As for "don't work any better", original-type seals on the T160's were a nightmare; the left on in particular never lasting very long - I put that down to the fork twist induced under braking by the single caliper. Certainly, since I fitted twin front calipers along with the Leakproof seals, I've never had any more trouble.