The 10K refers to the spin rate of the drive 10,000 RPM and the Ultra 320 is the latest SCSI interface. If you require 24-7 extreme reliability combined with very high speed, the Atlas family is for you. The latest version, Atlas IV is available in 36, 73 and 147 GB capacities.
The entire family shares the drive characteristics; 4.3 ms seek time, sustained data rate up to 72MB?sec and an 8MB cache. Of course it is S.M.A.R.T. compatible and provides thermal warnings. Drives do not usually fail catastrophically at once, but degrade over time. The inherent capabilities of the drive will alert you to problems prior to a data loss condition. With its annualized failure rate of 0.7%, the Atlas is a highly reliable device. It has a 5 year warranty, and my prior experience with Maxtor drives gives me great confidence that the warranty will never have to be exercised. One unique feature is the MaxAdapt circuitry built-in the drive. This is a closed loop system that improves signal quality to provide lower error rates and increased bus efficiency.

I installed the Atlas on my Athlon 2700+ system running under Windows XP pro. A word of caution, to those new to SCSI hard drives, install the SCSI controller before adding the first SCSI device. There is no software supplied with the Atlas, the drive must be prepared for use with Windows XP by using the operating system itself. You do this via the Control Panel, open Administrative Tools, Then Computer Management and finally Disk Management. The Disk Management allows you to prepare the drive for use. With Windows 98 SE, you can go the old fashioned (for me, more familiar) route of FDISK followed by Format from the DOS prompt. I tried both methods on the Atlas and both worked just fine.
Now comes the good stuff. I transferred files of differing sizes and types between an IDE hard drive and a USB2 hard drive and the Atlas. For smaller text files, there was not a significant time difference, however when I got to large graphics and HTML files, the speed of the Atlas showed itself. The IDE drive that I used was a Western Digital 5400 RPM drive; the USB2 drive was a Maxtor 7200 RPM drive. The Atlas gobbled up data much faster than the IDE drive, if it were a race on an oval, the IDE would be lapped very shortly. The USB2 drive was a respectable second, but the Atlas was a clear winner. I then decided to fill a CD with a video file. I used a Plextor 52X CDRW and sent the same file from each of the three hard drives. The Atlas is now my drive of choice for transferring video files.

The bottom line is: those with a need for high reliability, speed data transfer will be very well served by the Atlas family. My experience with Maxtor drives over the years gives me high confidence in the long-term viability of the Atlas. I am still getting reliable service from a very old Maxtor 500 MB hard drive, that has been in continuous use for many years.