That's the way that I feel, use what works best for each user. Security isn't a all-in-one package for everyone. If there were such a thing, that would block all bad code, either a single software, or multi-layered approach, that worked 100% of the time for all, we'd all go for it.
I've yet to find any single solution that catches everything 100% of the time, but with my combination on Windows 7 (& below) & Windows 8 CP (a different approach), does quite well. I've checked behind all, with different online scanners, no bad code has been found.
What works for each user, that he/she feels comfortable with, and will keep updated/configured & used properly, is the best approach to each users unique security needs. I've seen many arguments over security in many different forums & other articles, and I choose to stay away from them. It's all a matter of personal preference.
The same with Windows Backup & Defrag software, many users choose from a variety of paid & free software for these also.
Cat