Well, spec-wise.. The Huawei Ascend is the most impressive, it will be the fastest.. and it sports Android, you'll have access to many more apps than you would on Windows Phone (HTC). The Galaxy S will have access to apps, but not to updated Android builds. It will only be upgraded to Android v2.3 (Current version 4.1)
The downside to the Huawei is the build quality, made from plastic, and does feel very premium when held in hand if you know what I mean.. Not the feeling you get when you hold something like the iPhone, or Droid Razr.