I must be bad at explaining. You are doing the battle in your post. Here is my first battle.
Ultrafire M5 vs Olight I3s (picture when they were both brand new. I3s anodizing does not look that nice after living on my keychain)
Both AAA lights.
I3s is the shorter and skinnier light. Its also got the shortest reflector, which I prefer for a close up light. Both lights can run on 10440.
I3s have 3 modes and hidden strobe. Build quality is also nicer. I paid 1,3$ for the M5 and 6,99$ for I3s. Yes, both bargain prices you are not likely to find.
Ive had 2 M5`s with a few emitter combinations (stock XP-G, de-domed XP-G, XP-G2 3C, WW Nichia 119A) My I3s have had CW XP-G2 (stock). Nichia 119A and then Nichia 119B, both 90+ CRI and NW.
My M5s were gifted, I3s is living a life on my keychain.
I3s is the overall better light, and the winner of the battle despite that regular price is about 2,5 times higher. I think its worth it if you use the light a lot. Having many color options is also a nice bonus. :)