I'm not familiar with the specific formula, and Googling found a couple different results, so without knowing which brand/composition/etc., can't give a specific opinion. So, as a more general opinion:
If an athlete takes a protein supplement to accompany his workout, there's nothing wrong with that, since it's not cheating to the top, but simply providing the body with the nutrients that it needs and which may be lacking from the rest of the diet. In the same way, if this is a formula which – whether by means of herbs or straight vitamins or something else – is providing the mind and body with nutrients or other things which are lacking from your regular diet and life, then personally I wouldn't have a problem with it. As an example of one that would improve mental function for most people: Vitamin D. A very very large number of Americans are deficient in Vitamin D, especially those who work office jobs and as such are rarely exposed to the sun, so the body has little opportunity to manufacture its own Vitamin D. So, if you took a herb or vitamin or other mixture that basically just provided Vitamin D and, by doing so, improved mental function, there wouldn't be anything wrong with it. All you'd be doing is making your body more healthy and compensating for the unhealthy lifestyle that your career induces. Probably if your doctor tested your Vitamin D levels, he'd put you on Vitamin D anyway. There's others, too, so I'm not saying “if Focus Formula is Vitamin D and Vitamin D only then it's OK”, but just using Vit D as an example.
However…some athletes also use harmful steroids to artificially push their body beyond its natural limits. If Focus Formula has drugs that are a closer equivalent to harmful steroids, then I'd steer clear of it.
Figuring out what's restoring you to health and what's pushing you to an unnatural state is hard. Personally, if Focus Formula had things in it which would put a strain on my kidneys to process, that'd be my instant answer that I was going to avoid it.
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