The bottom ones are the wheels found in this thread. I know that, because it's my bike pictured. Someone else posted that they got the same wheelset, and the rear hub cracked, but we're still waiting for photos and the full story. I've had no problems with mine.
whats the difference between machined and non-machined sidewalls?
Machined have a ribbed metal surface for efficient braking.
Non-machined do not have a specific surface for braking, so if brakes are used, they will be in contact with the anodized/powdercoated sidewall itself.
The bottom rim is machined, the top non-machined.