Looking to get front end weight down.
If you do any kind of street driving I would leave them in. One of my friends cut his out of his race car (race only) and now wishes he didn't, due to all the crap that flies up under the hood...everything gets dirty. He said it was not worth the trouble or the weight savings since he had to put tubes in place from the fire wall to the frame rail for stiffening...kind of a wash. The only benefit he liked was it was a little easier to work on the engine.