First never heard of it, not in UK anyway. May be new to me as I've been retired for some years so ask about this in BUILDERS MERCHANTS not DIY SHOPS/STORES.
Don't rate plastic got it on bungalow moved into and few joints leak so had to bodge seal as no rubber seals available.
Think metal it's dearer and slightly heavier [aluminium is best] but you can paint it with paint for metal work 3 top coats inside and out starting with 1 or 2 primer coat. Done before you put it up. You can forget it for years and years if you do the joints properly. However if you settle for plastic then add one more bracket than they say to each length to ensure no sagging under weight of snow[ if it gets that bad]. Seen it happen skimped on brackets big sag and joints popped apart.
Post how you get on!
bob
May 2009
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