Companion way

The alternative would be polycarbonate. IIRC, polycarbonate is more likely to scratch than Perspex, but less subject to UV damage (crazing) and is more resistant to violent force.

Since I'm of the belief that I want enough strength to keep out a casual thief, and to convince my insurer that a determined one really did break in, without destroying the boat, that latter quality is irrelevant to me.
 
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