I've only used this a few times with standard loose tea leaves and it does the job very well. The mesh is very fine and although the odd bit of dust or extremely fine tea leaf escapes, there is no Great Escape of the tea leaf kind in your cup of tea. I don't know how it'd fare with fine leaf teas as I haven't used it for that but, like I say, the mesh is very fine. It fits across my mugs and cups perfectly and the saucer part is very useful both as a lid (although I don't often use it for that) and to place the infuser on when you've finished infusing and before you wash it up. Saves a puddle of tea on your worksurface! Four stars and not five only because I can't comment on its use for fine leaf teas but for me it serves its purpose perfectly.