I am thinking of buying one of these for product work, maybe fashion too.
Has anyone tried one?
For the price it is a lot cheaper than a ring flash, it takes a little getting used too, but it works well, it gives the ring flash effect, it also is a nice light source when not shooting though it, As Joe says it may be harder to use for macro were manual focusing maybe needed,
For fashion I have in the past use it by mounting the light on a monopod which makes it easier to focus and recompose during a shoot,
As I have lots of different light attachments I might sell this if you are interested in it. so before you buy give me a shout, 
Yes, use one for both.
A bit limiting for both if Im honest but does a job. For products works quite well for macro in conjunction with a light table but is frustrating to work with for close up work with manual focus (no access to focus ring etc) so I dont use the in built camera bracket preferring a tripod and geared head and then poke though the ringlite on a light stand.
As with most things studio, its a good thing to have even if its just for the odd 'I wish I had a x' moment.
