So, tested both, Cinnamon and MATE and came to the conclusion that MATE works much much better and, what's most important for me,is nuch more stable. After one week with Cinnamon on a fresh Mint 14 install on a physical harddisk, I made the following experiences:
Cinnamon is very complicated to configure and to modify, downloading extentions etc. and unpacking them somewhere manually and restarting the desktop is so old fashioned but maybe due to the completely borked Gnome Shell that is used as base for Cinnamon. To make all configurations I wanted, I had to look in 3 different places, dconf, cinnamon config, gnome tweak tool, that is a stauts taht I would cal subsuboptimal. Cross GTK version theming also is a big problem, GTK+2 applications look different than GTK+3 applications, and I haven't found a way yet to set a GTK+2 theme that really works in Cinnamon with GTK+2 applications. Panel/Desktop configuration in MATE usually is right click teh desktop or panel and select teh option you want, that's fast, easy and sane.
Cinnamon freezes a couple of times a day, in 90% of these cases, it is sufficient to restart cinnamon, but it causes complete system freezes at least 2 times a day, where i had to pull the power plug from my machine and power it up again. This is a no go for productivity systems and disqualifies Cinnamon for me completely. Under MATE, my DE never freezes or locks up the whole system.
Cinnamon looks great, very polished, but it suffers from the instable GTK+3 and insane Gnome Shell base it uses, you can chrome plate crap and give it a shiny polished look, but stilll, it stays crap under the shiny surface.
My DE is MATE, best DE out there for non mobile productivity systems, but this may change if MATE gets ported to GTK+3.x, as GTK+3.x means trouble and infects your system with a lot of Gnome 3 badware.
Systems: Mit 14 64 bit MATE on a separate HDD, Mint 14 64 Bit Cinnamon on a different separate HDD, both on a AMD FX8350 powered 16 GB RAM System using a nVidia 580 GTX 3GB with proprietary driver.