I just got back from Lucy's where three of us at work had orders. I probably go there about once every week or so as I work in Uptown Kingston.
I find their burritos are consistently a good size, the ingredients are fresh, and tasty. They just expanded their menu as well.
For good regular dinner Mexican Food in Kingston I recommend the Acapulco Grill Downtown on Broadway. (I'll write more about it on a entry for that restaurant though).
I prefer lemon to lime in the recipe.