Conclusion
The Cheetah 18XL's lower platter count and lighter actuator assembly results in noticeable benefits when it comes to heat and noise. The drive's seeks are a bit more muffled than those on the Cheetah 36LP. It still isn't, however, whisper-quiet like many of today's ATA drives. The drive operates relatively coolly for a 10k unit. Used in a well-ventilated case with decent space (say, an empty drive bay above the 18XL), the drive becomes warm but not hot to the touch.
In conclusion, the Cheetah 18XL does indeed prove to be a faster performer than the same-generation Cheetah 36LP. Kudos to Seagate for choosing to go with a separate name! More Kudos to Seagate for actually producing a drive that once again makes the venerable manufacturer a contender in the "fastest drive" stakes. Those needing a large-capacity drive or a drive that excels in file server or database usage would still be wise to look at the Quantum Atlas 10k II. If you don't need more than 18 gigs of capacity on a single drive, the Cheetah 18XL is the drive of choice when it comes to workstation usage.