The answer is no if:
- Your incandescent light sets are in good condition.
- You have (or know how to get) spare bulbs for your current lights.
- You use the lights sparingly...
- Only a few hours per day.
- Only a few weeks per year.
- You use the lights indoors only during cold weather days when you heat your home.
So by all means trade in your traditional incandescent lights for the new LED lights if:
- You use the lights outdoors or in unheated areas.
- You use the lights when the weather is warm.
- You can't find replacement bulbs for your current set.
- The wiring in your current set has cracked or missing insulation.
- You use more lights than your house wiring can handle...
- When you turn them on a fuse blows (or the breaker trips).
- The outlet or extension cord feels very warm.
Besides, the LED light sets that I've seen have an annoying flicker to them. LEDs turn on only when current flows in one direction. They remain dark for half the cycle unless a special "full-wave rectifier" has been included in the design. Unfortunately, the packaging won't tell you anything about the design, so you have to take your chances. Be sure to buy light sets at a store with a good return policy and save your receipt.
I hope this helps you in some way!