It all depends where you travel, as they are not available everywhere.
I used to have the following ranking of choice for stays:
1. Hilton
2. Sheraton
3. Radisson
4. Hyatt
5. IHG
6. Marriott
But now it is:
1. Hyatt
2. Sheraton
3. IHG
4. Hilton
5. Radisson
6. Marriott
Unless I start seeing some positive changes, they will fall even farther.