Today is my second day with LMDE. Yesterday I got it installed and now I'm trying to get more familiar with this distro.
Performance
I really like how LMDE runs. After boot it takes only 264 MB of RAM, Gnome 2.30.2 is snappy, responds quickly. The only thing I've observed was that when Gnome's compositing is active other apps suffer, like flash-player (videos on youtube are kinda slowed down on 720p), or some games.
Oh, by the way, I had little problems with the flash-player-plugin. It's nice that I had it preinstalled but something was wrong with it because on grooveshark – which uses flash – the sound was metallic somehow, the quality was affected. So, I switched to other package (there are like 3 packages with flash-player – flashplugin-nonfree, flashplayer-mozilla and mint-flashplugin).
I finally got fixed the reboot problem too! After a shutdown all was fine. I really like how LMDE uses kexec to hot-reboot!
I've tested how easily I could set-up and use the USB dongle 3G modem from my ISP. It proved to be a piece of cake! Again, I was pleased to see that my ISP was in the providers list.
Just for fun I've tried to install another DE, KDE and I was once again pleased that there was a pretty new version (4.6.4) and that the installation went smooth, a few minutes later fiddling around in KDE. Of course, now I'm back on Gnome!
Miscellaneous
Yes, I've now configured the fonts to my taste. I really love how LMDE looks! The colours are elegant and eye-pleasing and that menu is really useful. Everything is at a maximum of 2 mouse clicks.
The repositories are abundant, there's Skype, flash-player, Chromium and so on… Another big plus for that for LMDE!
Conclusion
The sun is shining! LMDE starts to look more and more like a very good distro! Tomorrow I'll get back with maybe more tests and the final conclusions.