Does not work

I bought this with high hopes, but unfortunately, it really doesn't work (at least for me). The main two ingredients are alcohol and water, which is about what you'd expect for a fixing or setting spray.
The Amazon page suggested that this spray would both set makeup, so that it lasted longer, and also prevent sweating. Notably, the bottle doesn't say that it prevents sweating, it just includes the claim that it 'allows makeup to stay on longer'.

I found that it did not prevent sweating in any way, and it didn't make my makeup last any longer. The biggest problem though - even more so than it not doing what it said it would - is that, after a few hours, make up set using this spray would begin to develop a really unpleasant and noticeable texture, kind of melting and falling apart and developing into little flat clumps on the skin. The only fix is to completely remove all makeup and start again. You can't try to fix it by applying other makeup over the top to smooth it out, as the spray causes all makeup applied over it to do the same thing.
I partly wonder whether this spray is only designed to be used over Mehron stage makeup, though nothing on the bottle or in the online description suggests as such.