Senior here.

Contrary to sdsearch's experience, I find that IHG Rewards points can often offer substantial savings over a property's after-tax rate. (Point stays are exempt from most taxes.) Points are often available for purchase from IHG for 0.5˘ each. The savings for credit-card holders can be even greater on longer stays: the IHG Premier Mastercard® offers the fourth night free on a four-night or longer points redemption.

It's easy to compare the after-tax cash cost of a stay with the cost in points at ihg.com, or on the IHG app, so one can plug in the places and dates where one might typically stay and judge for oneself. And the IHG card automatically confers IHG Platinum (mid-tier) elite status.

Edited to add: Of course, the cash price posted on the IHG website will not always be the cheapest available cash rate at a property. Sites like Trivago might come up with an even cheaper cash rate.