The slider just seems to knock a % off the standard room rate. For instance, if a standard reward is 80,000 points and room rate is $800, 40k points will knock $400 off the price. That said, $.004/pt isn't a great redemption, although it's not the worst. You can usually do better. You are better making the whole reservation with points at a place like La Quinta if you can so you don't have to pay the resort fee.