Pros: No smoothing, No jitter, No input lag, Detached mouse buttons allow you to click faster, Very cheap, Lightweight construction, Overclocks to 1000hz.
Cons: 125Hz Native polling rate, Only one DPI setting (450), Mouse button rattle, Sloppy scroll wheel.
It's one of the best all-around mice I've owned and I own a reasonable collection.
The good things about it:
1. Probably the most responsive mouse you can possibly own, even now.
2. No prediction or smoothing (No stupid ARM processor).
3. Literally no jitter (somehow?). http://prntscr.com/4smjp1
4. Detached mouse buttons made me click noticeably faster (went from 6.5/sec to 7.5/sec).
5. It's pretty darn cheap albeit you can only get it second hand now.
The bad things about it:
It has two "three" significant short-comings
1.Sensor Resolution (DPI)
You are capped at 450dpi so if you play on a screen over 1080p you are going to feel the burn.
Using a high sensitivity with low DPI can cause stuttery movement.
2. Malformation Speed:
The MLT04 is most known for it's relatively low malfunction speed, I have yet to test this but I haven't had an issue yet.
Around 1.65m/s Personally I find it acts more like crazy negative accel rather than seizing up like a zowie would, subsequently I find it much more manageable even at 70cm/360.
3. Random button presses/scrolling:
I played CS:GO with it at 70cm/360 and 50% of the time I put the mouse down it would click or change weapon.
and a few minor niggles:
1. Mouse button wobble since they are detached they can obviously flop around a bit.
2. The back of the mouse is a slightly wider than the front, personally I prefer flat, uniform sides since it doesn't force my hand into a predetermined position.
3. The scroll wheel is very sensitivity and sloppy.
4. The cable is thick and pretty heavy.
5. You have to overclock it instead of having the native 1000hz support we've come to expect.
A MLT04 mouse is a must-have purely to know what an unsmoothed mouse feels like, it's cheap and gives you a benchmark for what a sensor SHOULD feel like. Just make sure you overclock it to 1000hz or you are really going to miss out on what it is capable of.
Make sure you get a WMO 1.1 and not the 1.0, apparently that version sucks.