Armoral will not prevent cracking, and in fact will quicken it. The evil in
this and related products is silicone. Over time, the plasticizer in the top
layer of vinyl (which keeps the vinyl pliable) diminishes. Silicone oils attack
the top layer of vinyl, speeding up the process of deterioration.
To protect vinyl from UV, you should use a waterbased protectant such as "303
Full details of the products as well as the techno background can be found at
/// firstname.lastname@example.org mailing list
/// or try http://www.team.net/cgi-bin/majorcool