Hard-drive seek noise is not something you will avoid with this case. I can't comment on the stock fan configuration, because I replaced the PSU with a Corsair SF-450 and the fan with an Akasa 15mm PWM fan.
The airflow is relatively ok, the exhaust fan is directly opposite (and pretty much centered on) the harddrive cage, and the backplane is organized in a 3x2 configuration so it leaves some room for air to pass between the drives. The motherboard is flat on the bottom of the case, so doesn't impede the airflow, but also doesn't benefit much from it. If you need lots of CPU power, an active fan on the cpu cooler is recommended.
The drive cage itself and the trays are metal with hard-plastic rails, similar to QNAP, but the build quality is surprisingly solid. There's no audible resonance from the case due to the spinning drives. The case feet are padded with soft foam, vibrations don't travel from the case to the shelf it's resting on. I expect it will take a year for the foam to compress, but it's a nice touch. Other than that, yes, seek noise is pronounced. It's not something that bothers me because it's not in the living room, but I wouldn't want to put it next to my HTPC set.
My main criticism is the chosen positon and form factor of the power supply: it's mounted at the same height as the drive cage and projects inwards, leaving almost no room for the hard disk connectors (angled molex connectors for HDD power are a must!). They should have used a Flex-ATX form factor instead of SFX, and mounted it length-wise across the case's back plane. I have half a mind to get a Dremel and do that myself, but the other half is winning out for now.