The shots you've uploaded look fine as they are. Your lens should be 100% fine, I wouldn't worry.
You should note that you did make a few mistakes with your request though:
1) You uploaded files at very low resolutions. It would be better to upload full resolution (or close to full resolution) JPEGS, or even the actual RAW files for examination.
2) You uploaded images that appear to be shot well above f2.8. If you want to see if your lens has any issues, shoot at a range of apertures (including f2.8).
Nevertheless, I seriously doubt you'll have any hardware-end issues. You have a great warranty with your lens and your camera. You have focus fine-tune adjustment if your 24-70 doesn't focus 100% perfectly with your camera body, and you have a warranty if anything ever gets out of line. If you do encounter any issues, you should give your gear the benefit of the doubt and check your technique first (ie. getting exposure wrong, or shooting at too slow of a shutter speed / poor hand-holding technique to mitigate camera shake at the chosen shutter speed, etc).