Essentials do get updates for bugs fixes but slower.I saw people complaining that total security ESSENTIALS does not receive program updates at same time as the full program. There can be quite a lag. Qihoo favors the full program. So if I was you, I would install the full program.
The essential one does not have any ads. I wonder what will you call avast which keep trying to shove you their paid products/cleaner/etc.I vote for avast free those annoying ads and banners in qihoo lately and those annoying pop ups from time to time Will start to agrivate you. Plus avast free has less , almost no false positives
What's false positive when the system is clean. I rather have false positive then let some unknown malware slip through
Popularity does not keep your computer clean and safe. Qihoo have always beaten avast in terms of protection/detection.Honestly in terms of popularity, Avast Free dominated on major countries compare to Qihoo 360.
In Detection rates, no doubt Qihoo 360 have edge compare to Avast but very minimal on differential points.
But for major practicality then check the necessary features for you between Avast or Qihoo 360.
I am a man of results. I will use anything that give me the results I want.