Like said on another thread here, the first couple to a few hundred pounds come off free for the most part, but not all. The lower level micro ounce counting is where a few dollars may fall but well worth it.
In the long run, it's likely to break less and carry the mail with less.

Wish I had the time to fiddle with a F.A.S.T project, I hardly have any time for my regular street thug now. Those guys are a cool bunch of Alley cats with Lab coats.

Maybe I'll start a S.W.A.T racing series (Special Weightless Antics Throughout) or (Sneaky With Aluminum Titanium) LOL.