The first year our contractor sealed it - afterwards, we used Thompson water sealer - ours did not turn yellow. I will say with the sealer it makes it more slick when it gets wet (rain, snow). We also power washed to get old sealer totally off and to apply new sealer. If you don't get all the old stuff off it seems to stay tacky.

Thanks for the advice jeannie01.........yes I certainly plan to power wash before applying.