I've been using Thin Lizzy for a long time now, having previously been a consumer of Natural Glow. I find it quite good on it's own but better used on top of a light foundation. Unfortunately with age both foundation and Thin Lizzy pool in the wrinkles between the eyes which is not very attractive. I'm not sure what the solution is yet. In any case Thin Lizzy does add a nice touch of colour and is very simple and quick to use and it is highly recommended by me for those reasons. It is also inexpensive and easy to transport.
I think most of all it does what the ads say it will do. It would be handy if the ads showed a way around the wrinkle pooling issue though, because this can be more aging!