Summary: It's fine when it works but now two have failed me within 8 months after doing only light duty as Time Machine backup drives. The warranty replacement process was smooth the first time but after paying $25 to The UPS Store for packing and shipping each time I'm starting to become concerned about how much owning this drive is going to cost me.
Excerpt: I'm using this drive for Lightroom and as a way station to my offsite backup. The thunderbolt port makes a huge difference. It's plug and play, light and just what I needed. It does get hot after 45 minutes or so.
Summary: I needed a drive with firewire and there is not much out there to choose from. This unit is a great size, seems to be of high quality, a bit heavy but works perfectly! I would recommend this to anyone.