This stuff is awesome. Saw this on social media, and thought this would be great for the gym(where chalk may not be used, depending on their policy).
Used this for pistols, and it works great. Definitely helps to maintain dry hands and get better grip on the pistol, but this is also dependent on the pistol platform you use, the ergonomics, are you taping your pistol grips, etc.
For gym use, this stuff is awesome to have on you for gyms that don't allow chalk. Now, there are trade offs when switching between the GRPSAUCE and chalk. Yes, chalk is superior(minus super glue) with getting a more aggressive grip, and it does last longer throughout a session. But, it is way messier and dusty, and a nightmare to clean up/off of certain pieces of equipment or some gym flooring. You have to understand from a gym owner's perspective and the gym setting, why sometimes they won't allow it. The GRPSAUCE fixes that issue, where you can be very discreet about applying this and there is literally no clean up of any residue off of the equipment you touch. You put a little bit of this right before your set, it dries instantly, and it will last you long enough to get that set or two done. You will need to reapply throughout a session though, especially if it is hot and/or you have pretty sweaty hands. Recommend you have a towel to dry your hands first and then apply, this can help prolong your usage. But, this does depend on type of workout you're doing too.
Overall, I highly recommend this product for those days you know you need a little grip assistance, that isn't going to give you more tasks with cleaning it up later.