Hi All,  This is an opinion.  I received samples of Roo Glue's Roo
Clear, National Casein's replacement for PVC-E glue (#4508), and
Spectrum's CP-0401.

I made three identical striker bellows and covered them with Schaff's
nylon pneumatic cloth.  I also made a fourth bellow and glued the cloth
with PVC-E glue.  Then I pressure tested the bellows starting at 5 psi
of compressed air.

I found Spectrum's glue had the strongest bond.  The cloth popped off
one side at 8 psi.  I have been using Spectrum's glue since then for
other bellows work and am quite pleased with the results.

Musically,
John A Tuttle
Player-Care.com
Brick, New Jersey, USA