It all depends on your style. I personally go for all live plants, but others don't like the maintenance involved so they go for fake ones.
The live plants are beneficial for your tank. They look great, give it a natural look, give your fish a hiding spot, uses the fishes waste for food, oxygenates the water. I'm sure there's more I'm missing but that's just some off the top of my head.
I'd suggest them, but only if you're willing to keep up with the maintenance. No one likes looking into a tank filled with holey, brown, melted plants.