
Trust me if you are going to use them to actually work then there really is no substitute for metal ones even though they are more expensive,
Although a lot of the things I buy from "Shapeways" are very expensive even though they are made of plastic,
I assume it is because of the very limited production run.
And when you read Alwyns threads you get a taste of why the shapeways products cost so much with all the test runs using expensive raw materials.
Shaun.