I've trialed all of them and what i've found is that:
G Data is heavy but has some useful functions like encryption. F-Secure got a horrible UI but really light, can't even notice it's there and fast scans. Kaspersky is kind of heavy and has a nice UI, but really slow scans. Norton, lightweight, nice UI and has a fast VPN but it takes time for their "Download Insight" to verify downloads, fast scans. 360TS very nice customizable UI, avira and bitdefender engine, has some kind of HIPS but their own engines are weak. I also tried bitdefender, it was light but their updates are really slow, their UI is decent and doesn't have many features.