I'm the type that will pay almost anything to play a course once. That said, I've played Dubs probably 30-35 times, including 7-8 times since the renovation. It's definitely worth hitting if you're in town.
Post-renovation, it's more difficult than it was before, but not much more difficult (it was no pushover before). I think it's a course where (depending on your level of ability) par isn't that hard, but it can be very hard to make birdie. 12 is a good example. There are some pin positions that are completely inaccessible, but it's not that hard to hit it in the middle of the green and make par from there.
I played it on Sunday and it was getting pretty burned out in some areas, but I think they'll have in shape in time for the BMW. The greens mark up surprisingly easy, and for a high end course, it seems to get a ton of player who have absolutely no clue that they're supposed to repair their ball marks. The bunkering is much tougher than it was before, but honestly, if you hit the ball at a bunker, you better hope it goes in. After Rees got done with it, you are MUCH worse off if you end up in the long grass sloping down into the bunker. Greens fees include cart, but I usually walk it, and it's a pretty tough walk. Probably the toughest walk of any public course in Chicago.
I'd disagree with Pat about the Glen Club (I think it's highly overrated), but if you're looking for other public courses in Chicagoland, I'd suggest Pine Meadow or Cantigny.
As for #5, I'm pretty positive it's a par 4 from all of the tees (for men anyway), but it's a really difficult par 4. It's long and uphill, and you can't bounce a 3-wood on to the green because of the big front bunker. It has a pretty generous fairway, but the second shot is brutal.