Depends on your deck. If you run mostly or all basic energy, then probably not. Regular draw + Castaway will probably cover it. However if you have special energies that your deck really depends on then energy search can be good IMHO. You might be able to get by with regular draw (TV Reporter, Copycat, Steven's, etc.) in that case, but Lass would probably be less situational.
How much energy you run is also a factor. In a deck with 10 energy Lass is going to stink ... but in a deck with 20 it's a better play.