If you want a toy that will last a life-time, steel and glass can do that. Glass is a little more delicate, but a lot less pricey. I have many glass toys, but I have yet to own a steel one.

High-quality silicone toys can last a while, but I don't know about a lifetime. I've heard that if you cover them with a condom during use and use mild soaps to wash them, they'll last longer.

For most vibes, the motor will break down after a while. Sorry, but it's just the truth. I had a relatively cheap jelly vibe that lasted for 2 years, and I would use it on high for an hour at a time a few times a week, but eventually it got weaker and started eating batteries like crazy. Better quality toys may last longer, depending on how you use them, but I don't have any experience that would qualify me to answer that question yet. less