I remember looking at kevlar gears about 2 years ago and didn't buy it because it was noticeably more expensive than the plastic ones. Now they're $4, right about the same price as the plastic ones. Maybe there wasn't a demand for it then, or maybe someone was trying rip me off.
If there's that little of a difference in price, then buy one. It's only .50 more.
Sorry about the misinformation.