The deck at the South Street Seaport Museum is of IPE, go take a
look. Great PIA factor for installing. The contractor will curse you
and ask for an alt.
We spec'd IPE for a deck project a few years back and were
warned by a wood supplier that when you spec it, you do not necessarily
end up with it, even though the lumber stacks are marked IPE. The
middle men tend to play games with the species at this point, to make
endangered woods something else, and to turn some "lesser" woods into
something they ain't.