There last week
I was in Chicago last weekend. With the 25% off with VISA rates, our rate at the Hilton Suites was $74 versus $126 for the Drake so it was a no brainer as to which we would choose. As a HHonors Gold, the Drake nevers gives me Exec lounge access. I always get the breakfast coupons there. Plus, there are no in-room beverage amenities. If you or your spouse requires an immediate caffeine infusion upon waking that can be expensive at the Drake if you don't have lounge access. I prefer the decor and 'feel' of the Drake in general, but you can satisfy that by popping in for afternoon tea! Also as Gold I usually get a little bit of a view at the Drake.
The Hilton Suites has a lot going for it. It doesn't have the charm factor, but it does have a View advantage. Lots of high rooms with city or lake views. Big windowed walls in the living room and bedroom let you easily see the sights. The Fitness center & Pool are on the top floor. It's a pretty standard hotel decor. The rooms are suites with 2 rooms, each with its own tv. There is a sink/bar area in the living room along with a microwave and fridge. So, if you are planning to stay a few days and want the luxury to spread out a bit and bring food back to your room then Hilton Suites is a good fit.
Breakfast-wise, to compare the 'free' breakfast (doesn't include tip) you get with the coupons, it is pretty close. Although, I think the Hilton Suites might have had a slight edge this trip since their fruit was fresher and more flavorfull. If you are comparing the FULL breakfast, then the Drake wins for me.
Hope this helps a bit. Also, there is $26 per day parking a block farther along on Delaware place which is half the rate for the official parking at the Drake and HT and is convenient to both. It's underground. My car was warm (50 degrees) when I picked it up which was about 40 degrees warmer than the air that day.