In a word, yes! You shouldn't be aiming for actual money returns, it should be percentage. What is the return on your capital? If you put the money into savings what would you get? 1-2%? The only consideration is if you're limited by how much you invest, is there a better product that you're not able to invest in by shooting for the 20%? But I wouldn't waste too much time searching or you'll never invest. I would go for the 20% then spend some time streamlining the process to increase margins once the product is proven. Good luck with it!