We measured a temperature of only 44 Degrees centigrade, which is an excellent result for a 7200 rpm drive. Only the Western Digital 205BA is running a tad cooler.
Again, the higher capacity DTLA drives (45, 60, 75 GBytes) come with 3, 4 or 5 disks inside. Due to the higher friction inside the drive you should consider that a drive becomes hotter the more disks it consists of. Generally, a brand new drive that offers the same or even a higher capacity with only one or two magnetic discs is a better choice than its predecessor with three or four.
Last but not least the noise level is very acceptable as well. In normal operation, you usually won't hear the DTLA drive. The 60 and 75 GB models will certainly be louder, as the higher amount of rotating disks creates more noise. Also the disk access noises will be louder with the high capacity drives, just because there are more heads working inside the drive.