I am all for removing animal products from the diet but that does not excuse lying to the consumer. If you think you have a great egg-less mayo like sauce, you should be proud of the fact that is egg-less and make sure the consumer knows it. Not hide it.
And no it does not taste anything like mayo. It has a weird spicy taste. Mayonnaise is not supposed to be spicy. Some people may like it, but the people that are expecting the taste of mayonnaise will be quite disappointed. I am willing to bet that a lot of food has been thrown in the trash because of this little marketing trick.