PC-Chips (including ECS) are fourth or fifth largest mainboard company in the world, so they're not exactly small.
A word of caution on PC-Chips: They don't do end user business at all. Meaning that if you buy one of their boards separately (not in a complete computer built by one of PC-Chips's OEM customers), you'll be on your own, no help, no manufacturer support besides a terse manual and BIOS/driver updates. If you can do with that, fine, the boards are OK, and you won't be able to build a system anywhere near as cheap as when using theirs.
If you can't help yourself in any kind of situation, choose a manufacturer that does retail business - if you like a particular PC-Chips board and want support, then have a look whether ECS or a retail outlet like Amptron or Matsonic carries that particular model.
regards, Peter