LWJGL or Unity, UDK, Cryengine

So I want to begin with 3D soon to expand my horizons in game dev. I was wondering what would be more worth my time. Should I use a do everything engine like unity or dedicate myself to LWJGL for a few years to learn ultra awesome 3D skillz?

What would be the most beneficial to my career and sanity :stuck_out_tongue: ?