It might be easier if you have a 3- or 4-wood versus a 3- or 4-iron. It's much easier to hit a low sliding fade with a long wood, and everything feeds down. The long iron compels you to fly it over the mounds.
We need more input on #18 Chambers Bay here. It's not a very difficult hole, if I recall correctly.
Here are the stats from the USGA archive:
Chambers Bay #18 listed at 604 yards, average score was 4.920, 3rd easiest hole, 2nd hardest par 5 (#8 harder, #4 easier).
For your information, #11 played harder, averaging 5.029 at 539 yards.
They plan on having tees to play both #1 and #18 as either a 500 yard par 4 or a 600 yard par 5.
Like I said, I think the green is kind of similar, concave and very high on the back left.
http://www.golferswest.com/destinations/chambers-to-modify-par-on-two-holes/