Here's a strange one: A friend has a CZ 75B made in '96. His recoil spring guide is metal. I have a CZ 75B made in '98. This guide is some kind of plastic(polymer?). What's the deal, and should I get a metal guide? No functional probs, I just wonder why the change in materials. Also, anybody try Microlon Gunjuice and, if so, notice any improvement in accuracy after treating bore as the ads claim? Thanks!