Great for your hand, terrible smell
I drive 3 hours a day in the car and I got this to work on my grappling strength for jiu jitsu while I was on my long daily commute.  For that purpose, it's great.  I used it for all five fingers, but you can also use it for four fingers against your palm, etc.  So I would give it 5 stars for that.  However, it smells...a lot.  It actually smells like a cheap perfume or vanilla or something.  It's not a bad smell like plastic, but it's so strong that it fills any room you put this in.  I finally had to remove it from my vehicle because the entire interior of the car smelled.  I put it in my garage and now the whole garage smelled.  I thought after a couple of weeks the smell would fade, but after 1.5 months, it's still going strong.  I don't know why they don't make air freshners out of this stuff because it sure lasts longer than most air freshners.  For that reason, I give it only two stars.  If you only use it outside, or you can easily store it outside after use, then I say go for it.
Rating: 2 stars