Western Arms are outdated, I don't even know if they're still an active manufacturer.
I can comment on the plastics used for their 1911's, they're similar to Marui but the internals are a little better than WE 1911's. I owned a WA M1911A1 Magna Tech, I can definitely vouch for the Marui 1911 only because of the availability of spare parts, upgrade parts, metal kits, better quality overall and the availability of spare magazines.