I Really Like Mine
1. Max-Prop, two blade. Have had it for some 17 years now and still going strong.2. Don't get any "clang" when I put it in gear. I sail with the transmission in reverse and start the engine with it engaged in reverse. After starting then I shift into "forward". As for any clang noise I don't know what you mean but there is no noise that I remember.3. Non-metal blades: Max-Prop used to make a plastic/carbon fiber, or what ever, kind of prop briefly but discontinued it. You might ask them why.4. Results: EXCELLENT. What more can I say. Wouldn't have a SAILboat without a feathering/folding prop. I don't like dragging a sea anchor around. We've been up to 10 kts under sail numerous times (Hunter 35). I don't think you could do that with a fixed-blade without a hurricane.5. Corrosion: no different than anything else on the boat. Keep away from "hot" slips, hot boats, and keep the zincs fresh (I like to change mine about every 4 months although they've gone up to 6.7. Quiet: the feathering prop means your sailing is Quiet! No turning prop shaft and no swirling of water. Total quiet. And, the boat under sail just glides along.