I paid for amb with points and was upgraded for a reward stay at the ic Prague. It was worth it in my opinion because I had points to spare. And with the ihg cc I received 10% back on the points. Later I became spire and got the 25k so really being amb costed me 2k points. I am not planning on staying in an IC for a while but when I do I can use the free night cert. that came with being amb. It was worth it to me and my needs. Good luck.