There is about 40-50 lumen difference between M60 on one 18650 and two 18650 cells, so I think it's in the 180-190 lumen category. Not bad but there is a visible difference.
M61 is a much better module to run on 1x18650. There is no obvious difference between 1 or 2 cells.
However my all time favorite is M60L. You get a solid 4 hours of runtime and a very nice hotspot with throw. If you don't believe me, superimpose the beam of one to another and you see how M60L dwarfs M61.
M61 is actually less bright than M60L *at any given square inch* meaning that M60 or even M60L will throw more, of course the *total* lumen output is far greater than M60L. Truly, M61 has more of a oh-my shock effect than anything else, short range anyway. Truly a wall of light.
I don't think you can go wrong with *any* Malkoff module to be honest. For example M60LL or M61LL is supposed to give you super long runtime, about 20 hours on one 18650 cell, while still maintaining a good lumen level (40-60?)