I have the Olights M30, M3X, SR51 and big daddy SR90.
The M30 was my first Olight and it did me years after being disappointed in Led Lenser lights that I still own.
The M30 is a "wall of light" in that it is very floody and not a great thrower but the strobe button on the side is handy.
The M3X is a great thrower and pretty good spill.
The SR 51 is another great thrower at 900 lumens and also has plenty of spill.
Of course the SR90 is a different kettle of fish, all weight, throw, spill and just pure power and around $500!
The M1X is pretty old technology now but was a leader in its day.
Simple solution, it a comes down to whether you want throw or flood mainly.
The M1X is still good as a spiller and cheaper nowdays.
The Olight M30 is a wider beam which I use the battery extender on to use 2 x 18500s.
Personally my favorite all round light is the Olight SR51 (900 lumens OTF).
It has a high at 900 lumens and low at 200 lumens and access to the strobe pretty quickly and comes in a great Aluminium Case with the accesories to keep everything together when travelling.
The SR51 comes with 2 battery carriers 6 x CR123s or 2 x 18650s and uses the CREE XM-L (U2) LED.
I use the 2 18650 option in the SR51.
And also the Olight SR50 uses both battery carriers as well and has an SST50 LED in it.
It too is a great thower and comes in the same type of Aluminium Case that the SR51 uses.
If you like the thinner style rifle mount type flashlight the Olight M3X is still tops and a great thrower with spill IMHO.
The M1X is old technology now and these later lights are heaps better in output, using mostly XML Leds.
The older lights are rated under the older system and both don't do much more than 450 to 500 lumens in real OTF lumens as per the later ANSI standards.