Having owned SiS, VIA, and ALi, I can say my preference (right now) is still VIA.
Pabster says, "Just look at the number of VIA issues crowding any given discussion board"...he could equally say "Just look at the number of
idiots crowding any given discussion board."
VIA is by far the most prevalent third party (not Intel) chipset maker in the industry so it shouldn't be surprising to see so many threads for VIA on these boards. Let's remember that virtually no one comes to these boards to post on how great their motherboard is running. They come when they're having trouble...which means the odds of an idiot getting a VIA board and posting about it far exceed those getting SiS or Ali.
People pine on and on about how many issues VIA boards have. Here are some of the major ones:
VIA 686B + SB Live = HDD data corruption, playback errors etc. (fixed by 4in1)
VIA + WinXP + Det 23.11 drivers = memory instability (fixed by 4in1)
VIA + PCI ATA133 controller cards = lowered IDE performance (may not be driver-fixable)
Beyond these there's not much else to cry about. The first two can be fixed, and the last one is fairly uncommon on the home desktop.
That doesn't mean that VIA shouldn't be taken to task for these ingressions, just that they're not as disastrous as some would have you believe. The performance of ALi is lackluster at best. Even their newer B0 stepping can't outperform the venerable AMD 760 chipset, whereas the KT266A sports the fastest DDR memory controller on the market. Some may argue that it's worth giving up performance "to save yourself a hell of a lot of headaches" but the reality is most headaches aren't from the chipset, but from the builder's actions.
The 735 is a worthy chipset that was adopted by vitually no one. ECS is a joke, I don't care how many boards they sell. One board (completely ignoring Chaintech's sad little 735 board) with no real overclocking options*, no RAID, an entry level BIOS, and one of the worst manuals I've ever read is not the freedom of choice I enjoy. I'm hoping that SiS will be able to take off with the 745 and power some of the names associated with quality like ASUS, Epox, Abit, MSI etc. They need to...Silicon Integrated Systems Corp. is carrying a heap of debt, and they need to stick around to keep a spur in backs of the other makers.
Here's a good link comparing the chipsets in question