Jeff,
I was once dead set against them, and yes, a true 90 usually looks awkward.
But I have designed a few at 70 plus degrees, sometimes against my will that I have turned out to like, such as the 15th at Tangleridge or the 15th at Bridges of Preston Crossing.
The beauty of them is that hitting the inside of the fw, whether guarded by lake (TR) or grass bunker (Bridges) vs playing safely to the outside is greatly maginifed. Given a 40 yard wide fw, the risky tee shot is automatically 3-4 clubs shorter than the safe shot.