Treated like Royalty eventually.
Background: My friend and I scored 2 FREE night's stay to any Hilton hotel when we joined a Twitter contest in San Francisco. I was part of the first 75 people to line up by 430pm on a September 2011 day and got a voucher for a FREE hotel stay! We wanted to go with Waldorf Astoria but it is far away from Downtown Chicago, so we opted for the CONRAD. I've never stayed in a fancy hotel such as this so, our expectations were really high. 
Before we booked anything, we've been communicating weeks before with management via e-mail. We made sure our vouchers would be honored and that we can upgrade and pay the difference. When we checked in at 6am (we flew red eye), we were just hoping to leave our luggage in the hotel and be given our promised upgrade to an executive suite. This is when we encountered a bit of difficulty with Ron at the front desk. There were 2 men at the check-in counter. The first man said that the upgrade would be honored. Then, Ron stepped in and said that it is NOT available given the type of payment we had and that because it is a busy weekend (we were there over President's Day Weekend), the room is (suddenly?) not available. We reminded him of the e-mail exchange with another manager and he said that he'd have to speak with them since maybe that person was misinformed. We then handed over our vouchers and he starts asking why our names aren't on the vouchers. This is when I started getting internally angry since he was making it very difficult for us despite the previous communications with management. We had to remind him of how promo works and that Hilton gave out these vouchers randomly. I started taking down notes such as what his name was and all the things he was saying.
I think this is when Ron realized that he needs to fix things quickly because you do NOT want a BAD review or upset guests.
With that said -- Ron made it up to my friends and I BIG TIME. As he should because, we have evidence of e-mail exchages and Twitter re-tweets to score this voucher. As such, we were treated like Royalty eventually. 
The first night was a Standard Room with 2 beds and a free of chage roll away bed. We were given tons of pillows and 5 free drink tickets which cost around $15 each. The next day, we were finally upgraded to an executive suite like we've been promised for free. The suite had a queen size bed and a bath tub. Both rooms had great views of the other buildings. I love that you can order endless bottled water and can request a Keurig coffee maker. 
The location was perfect -- within walking distance of the major sites. We didn't even get to ride the Metro since cabs were fairly reasonable when we split it amongst us.
All in all, I would recommend this hotel despite the hassle at the beginning. I would however suggest that management be more accurate with giving out information so as not to upset guests.
Thanks for everything, Conrad Hotel!! Best FREE hotel stay I've ever had.