Review (5/5): have used it for years and love it!
i have used this product for several years now and am purchasing a refill. as a strawberry blonde, if i don't use some sort of tint, it looks like i have no eyebrows or eyelashes at all.
having read some of the negative reviews, i have some application tips that may help:
--for storing and mixing: i found it best to empty all of the capsules into a small lidded jar b/c i never use an entire capsule and it's just messy to open, close and reopen the things. i use an old contact lens container for mixing and apply with a short-bristled, flat-end, stiff makeup brush.
--for eyebrows, go conservative. i usually only let it stay on for a minute before rinsing it off. to prevent too much dying of the skin, apply the tint, use a moist cotton swab to remove excess, then before removing, rub the tint/eyebrows with just soap, no water, then rinse with cool or lukewarm water. the color will actually develop further over the next few hours so if it doesn't look dark enough right away, give it a little time before going back and doing more. if the surrounding skin does stain, use straight peroxide on a cotton swab to remove it then rinse. you may not get it all off but it'll help.
--it's not supposed to be for eyelashes, but i use it there as well...very carefully. i apply with the same flat-end brush and leave that on for a couple of minutes. so i'll apply to my lashes first, then after a minute or so, do my eyebrows and rinse it all off at the same time.
--it does not last six weeks, though mostly due to new growth and only slightly from fading. it's really nice for fair-haired people b/c it allows you to go without makeup and not look like a ghost.