Yes. I have the previous gen Master MX. The scroll wheel is a solid metal flywheel. It has serious heft and continues spinning maybe 5-10 seconds after a good flick.
On mine, the horizontal wheel does not have this feature. Maybe the newer model does.
And like another poster mentioned, it has a detent when scrolling slowly like a traditional scrollwheel, that then mechanically disengages when flicked fast enough. You can configure this sensitivity in software, and even map one of the mouse buttons to disengage the detent, if you dont like the smart scroll feature.
Its seriously the best designed mouse I've ever used. It's clear logitech spent a lot of effort thinking about what makes a good mouse really good, and they implemented that in this mouse. Truly a flagship device, without cruft or unnecessary crap.
Battery life after about 4 years is so-so, so I keep a usb cable on my desk to plug it in when it runs low. I get about 2 weeks out of it?
Materials are also degrading a bit, it's surface is becoming sticky like many "velvet" finish plastics do, but its not at a point where it's gross to hold.
Its held up very very well after roughly 1000 work days of use. It's cost per day of use is basically 0.
