Used this twice recently. Both places I had been trying to get BRG's for 6 months with no luck. For those that don't know, it costs 1000 starpoints per room for max 5 nights. Fully Flexible and get points back if you cancel.
Prince de Galles, Paris France. 5th-9th Oct. 2 x Art Deco Deluxe (including rollaway) $567 EUR AI (think this was 35-40% off best price I had found).
The Chatwal New York. 24th-29th Dec. 2 x Junior Suite $563 + $50 (rollaway) + Taxes. This is about 35% off the best price I have found in last 6 months for these dates.
As you can see, saved us many thousands.