you will produce nice enough stuff with your system spec, but yes there is a lot better and therefore a lot more expensive.
For example I have a matrox real time editing card in mine, these are about 1,000 pounds and it makes all the difference when using premiere.
These more expensive systems you mention probably have stuff like this in along with dual processors, 2-4 gig of ram and probably 3 HDD. And yes when you pay 7,000 they will be more reliable because they will be built with high end reliable branded parts.
Probably not worth the money, but you get what you pay for. A lambo car spec maybe only 50% better than a RX8 just for example but then the price is 20 times more.
__________________ 2 x 21\" HITACHI super contrast monitors.....2 x 200 gig HDD\'s....2 x 512mb dane-elec pc3200.....TV in card (cheap and sh!t!)....3.2 P4 HT....BOARD - ASUS P4C800 - C delux (fsb 800mhz DUAL DDR 400)....GRAPHICS - ATI 256ddr POWERCOLOUR Radeon 9600XT (500mhz/400mhz)....MATROX RT.X100 real time editing card |