If its a short run kit, chances are the fit quality will be a major issue. As far as the plastics used, they probably opted for a softer blend to preserve the life of their short run molds.
More and more of the recycled plastic is making its way into industry...unfortunately it isn't conducive with many applications the product was designed for. I got a piece of equipment the other day which had a part made from this "green" plastic. The mfr already initiated a recall, sending replacement parts to consumers as they are learning this blend of plastic isn't performing as promised. Simple enough fix, but an inconvenience and a cost the mfr wasn't planning on.