I dual boot Ubuntu and Mac OS X on a brand new Mac Mini (late 2012) with OS X 10.8 and use a 2Tb external drive formatted as EXT4 with lots of large files. The copy of a 3Gb file to the ext4 external drive takes 30min on Mountain Lion and 48s on Ubuntu. A copy of a 5Gb file takes 48min and drives the CPU of the (quad)Core i7 processor to 100%. The whole computer slows down to barely unusable during the copy. Not to mention the file is duplicated at the destination folder with the same name or some times as a hidden file named "._name.extension". I had this problem for a while with version 8.0 and purchased the new version 9.0 of ExtFS only because I thought it would fix the issue. It was a waste of my money as the problem still persists. Paragon advertises here: https://www.paragon-software.com/home/extfs-mac/features.html -Unprecedented high level of performance thanks to the Paragon UFSD™ technology -Fast and transparent access to any ExtFS partition under Mac® OS XTM -Improved stability and performance And so far I didn't get any of those... Dos anyone have the same problem?