I have both, Depends on what you are looking for, single coil or a double. IMHO Lemo is easier to build and wick.
Right now I use my Billow 3 to 1 over Lemo.
They don't leak for me, And both perform very well.
I did have to put the Billow on a mech
mod with my current build. 30 Watts is just not enough.
I guess here is your answer from my limited experience. So much easier to drop resistance in a double coil than a single and go over 30 Watts.
If the Billow comes out with a split chimney, I will get one (or 3) in a heart beat.