I've been using this for a good while and had very little trouble. It technically only supports Ext2, But Ext3 is backwards compatible , so it can mount an Ext3 drive as an Ext2 (just without the journaling benefits)
If there's anything off with the drive (such as data in the journal waiting to be written), the driver will refuse to mount it and you'll have to fire up linux to patch things up. (Data in the journal is handled automatically at mount time by the Ext3 driver.)
This is a cool thing I've used for a long time, but I'm eagerly anticipating the addition of ext4. I don't know if this driver specifically has any plans to implement that, but I would like it. Anyone have any news on this?
And for the record, this has worked fine for a long time -- there were initially a lot of issues with running programs from ext3 in Vista, but they seem to have been ironed out for the most part. It even has a nice GUI to assign drive letters.
If there's anything off with the drive (such as data in the journal waiting to be written), the driver will refuse to mount it and you'll have to fire up linux to patch things up. (Data in the journal is handled automatically at mount time by the Ext3 driver.)