My Makita 9227C is all I have ever used and as already been said above, the speed of correction and smoothness is so much faster and easier on the joints..
I bought a new Flex 3401VRG around 10 years ago when it first came out, to see what it was all about coming from a big German company that polishes stone...
It was a pretty good machine for what it does, has more pad rotation than anyone else in the Random Orbital world, works like a beast, but you just have to get used to the counter-clockwise rotation and then you have it..
And like all Random Orbitals, there comes with it an amount of vibration, which after using for several hours non stop, will leave your hands numb sometimes..
I only use Flat Foam Pads, have messed around with the Microfiber but it`s too much trouble for my needs, and then you have to come back and clear up the paintwork, where I can get all the correction and clear glossy paintwork usually with 1 foam pad type..
There is a zillion compounds and polishes out there, I prefer Menzerna and Optimum, sometimes a little Sonax and Im good..
I will just stick with the Rotary Power and get very flat, clear as glass correction with no swirl marks, etc...
Dan F