awful, don't use it. it literally goes stale, too. i have a friend who put the bottle away for a while and took it back out a few months later and it was growing mold! apparently this is very common with leather cpr gross. not worth it, there's no way to get your money out of it, unless you clean hideous amounts of tack all day.
I bought some a month or two ago, so I am stuck.
I would still be interested in knowing whether you think is is good for tack or not.. Is it better than a glycerin soap?
If it is any good, I would use it for some things until it goes bad.
I have used it on some old leather that has not been used in years and it seems to have a good softening effect. In other words, it seems to be a good leather treatment.