Liz,
here are two shots I took with the 28-135 IS. For portraits, it works great.



That shot was taken on location with 2 strobes at F8.0.



Shot in the studio at F8.0, 2 Alien Bee 400s.

I think this lens is ideal. It's as sharp as necessary stopped down; it's compact and easy to carry; it has IS which is a real benefit when you're shooting at 135mm (which is really 216mm on a crop body). And it's affordable.

BTW, how do you like the70-200?

Jim