Polymer-based Flex Trim radius moldings generally cost one-third as much as comparable custom-made curved wood moldings, says the manufacturer. More than 8,000 standard profiles are sold in paint-grade and stain-grade versions. Unlike wood, Flex Trim is immune to damage by salt, moisture, and extreme temperatures, the company says. Also available is an upgraded product called Zzzz Flex, which can follow even tighter curves. Flex Trim, 800/861-0734, flextrim.com.