The "best" is something very dear relative. The ideal security solution will depend on the user profile (basic or advanced), usage profile of the computer hardware configuration of the machine and user ID with the security software adopted. There is no single answer to your question, because as you can see it is not so simple.
Friend, 100% detection would mean that we would have a perfect system, and this world we live in unfortunately we are far from perfect.
I think we should always seek a security solution that ensures the excellent level of protection, but also not forgetting its usability and low consumption of computer resources.
Avira Free Antivirus has an excellent base of detection signatures, and this is a consensus in the market. Moreover Avira lacks a tool for detecting very recent those threats for which signatures are not yet available that can detect them, known as time zero.
Avast Free Antivirus does not have signatures with the same quality of Avira, but otherwise has a detector behavior and a sandbox that can stop the attack of zero hour threats.
So you can not say that this is better than that, because each has its pros and cons.
Viewing the test result of Matousec realizes that Comodo, Emsisoft Karspersky and (despite not aprecer test) are the only really suites complete when evaluating each of its protection tools. BitDefender, G-Data, Avast, Norton, Vipre, Eset, Avira, Panda, AVG and Bullguard suites are good, but always fall short in some of its protection tools. Many have a great data base, but fall short on behavioral module, those which have good detection signatures and good modulus behavior leave much to be desired as regards the firewall.
Besides each ferremantas of Comodo, Emsisoft Karspersky and be efficient, draws attention to the harmony of tools when working together, making these the best existing suites.
I'm not saying that the other suites are bad, but by historical tests and realizes that they are not complete as the three mentioned.
At first module HIPS offers greater protection than a detector system behavior, but this of course will vary due to the quality of the product itself.
This is the case, for example, BitDefender Internet Security 2013 that has an excellent detection performance that is equivalent in quality to the CIS module HIPS or KIS.
In terms of security suite and beyond the CIS and BitDefender, I would highlight the GData Internet Security 2013 and Emsisoft Security Pack as other great options