"As most SCSI disk have a much higher RPM they have smaller access times which is the most important thing for every application I can think of apart from AV editing and certain server applications."
It's not an awe-defining performance difference and very much like paying 5 grand to give your car 15-20 more horsepower when working on a system where you open one or two or even three apps and work in one then the other.. I know my responses are cost oriented and the original response was cost really isn't a factor. It's just hard for me to say ok yeah go spend 600$+ with a strait face.
The drives really shine in servers where the lower access times in conjuction with bigger caches and controller caches can add up to saved time and ability to handle heavy access. And they do create a heat management issue especially in a mid-tower.
"SCSI to SCSI transfers don't use the CPU like IDE"
I think you mean memory addressing. Of course, yes SCSI has been using DMA for mm long time. And compared to PIO where the CPU has to route request, this is true. But times have changed, and this is just not true anymore with the UDMA specs and support in the OS for IDE dma. Especially now with the integrated or add-on dma controller cards.
So hey!! NO budget then do it! Grab that Cheetah X15 and burn it baby. Then you can say you got it!! Hard for me to justify that cost, but who am I to judge the color of a man's Ferrari? I mean it's a FERRARI! But if you get fragged online, it's likely that dialup and not your hard drive. I'm out and hope this all makes SCSI and IDE owners feel better.
***Hey I run Intel... but let's get real***