All-In-One Solution or 3D Platform?
To some extent the SiS chipsets are bohemian products. Being impressively integrated, they are much less expensive to produce than two-chip solutions. Therefore they seem predestinated for low-cost desktop solutions, as they come with all components a business computer might need: Standard 2D/3D graphics functions, a fast IDE interface, sound and even a network controller - everything is included for free. Having all of this on the motherboard clearly helps to economize the costs for the complete machine.
Surprisingly enough SiS decided to include an external AGP port as well. Thanks to that, you may equip a SiS730 motherboard with a fast 3D graphics card, making a gaming machine out of it. I can imagine that many users might be interested in a cheap motherboard with this chipset instead of purchasing a more expensive VIA solution. Right now it is clearly more convenient for gamers to save up to $50 on the motherboard and invest that money into a faster graphics card. The overall performance will usually be better going this way.
When studying the benchmarks please take into account that I used quite a slow processor, a Duron 700 MHz. That's one of the cheapest models available right now. Nonetheless this CPU is fast enough to produce good frame rates with current 3D games - provided that you are using a good 3D graphics board. Windows applications usually run fast enough anyway, so that software like MS Office can be left out of these considerations.
Stability and Drivers
I remember that a few years ago many people complained about reliability and stability issues of platforms based on VIA, SiS, VLSI, UMC and ALi chipsets. While VLSI has been bought by Philips and UMC does not design chipsets any more, the other three have lately provided reliable and stable products for quite some time now. I remember prototype motherboards running so unstable that you had to spend the whole night to get benchmarks finished. The SiS730 reference board did not cause a single hang up or any other trouble at all, which was a pleasant surprise, considering that it is still a prototype board. I have to complain about SiS' driver support however. Of course they have their own AGP and video drivers, but I was missing a refined IDE driver, which could have improved hard disk performance.