I was looking for an AA tube light too…until Acebeam sent me an M10.
See my review, but I will not lie : I really like it 
I LOVE the side switch and UI of my Olight S1A, but its head is a bit bigger than I’d like.
I LOVE the shape of the Klarus Mi7, but hate both mode spacing and UI…
I LOVE the simplicity of my Thorfire TG06, but it’s too big for its battery…
The M10 fills the gap, IMHO