I'm looking at buying a Dell Studio desktop. Have just started out in digital photography, shooting in RAW mode & looking to pp. Have purchased LR2. The system is as follows:-

Core i70-920 (2.66GHz, 8 Mb)
Vista Home Premium 64 bit (free upgrade W7)
1TB SATA 3.0Gb/s HDD
Dell S2309WFP Monitor
512Mb ATI Radeon 4850
8Gb or 9Gb DDR3 1066MHz memory

Just a couple of questions. The unit I priced with 8Gb ram was pretty much the same price as another system I priced with 6Gb (due to different discount offers). The 8Gb unit can be upgraded to 9Gb for approx. AU$100. Am I going to see any advantage in 9Gb. Also does anyone see the value in extending the warranty from 1 year to 3 years (extra AU$148).