"Hotwire also offers hotels that list a shuttle icon but Priceline will always beat Hotwire's price."

This is simply not true. There are hoops to jump through to get PL prices; sometimes the hoops have been collapsed by using up bids. Sometimes the star values between PL and HW differ. Sometimes the locations and zones differ.
If you know what you are bidding on, have compared hotel lists (hopefully updated), and do everything perfectly (from star to location to timing), usually PL can be a better option.
I can't help but respond to blanket statements, even though I know this is just another opportunity for persons to shill for their own business.