"Best" is a very subjective word loaded with variables. What are you looking for? Brightness or long runtime? Narrow or broad beam? What type of battery? Do you prefer the power in the back or all in the front? What type of switch do you prefer? Do you need to use it with a gloved hand? Are adjustable levels important to you? Do you like a top strap? Does it need to be waterproof? Do you prefer multiple cells or just one? Will it be used in below freezing weather? How do you feel about adjusting the angle?

My point is, your question is like asking what the best car in the $25K-$40K range is. As Jim said, the light should fit your needs and you didn't specify what they are. Without knowing that, any suggestion is a stab in the dark. Pun intended