Both are good. Just a couple of points that came to my mind:
Avast with Hardenmode (aggressive) is a nice white-list. They have a large database of good files (I rarely see false positves, and if I encounter one, I can easily add an exclusion). Avast free does tend to be high sometimes on marketing popups (depends on the month). Avast is a product that has been around longer. They have a behavior blocker , which SecureAplus lacks. If you use Hardenmode Agressive, I believe the behavior blocker is no longer used since it is using a strict white-list and doesn't care about the characteristics of files. Creating a password with Avast to protect against someone running a blocked file is easy. With SecureAplus, it is harder (you have to create a another user account). Avast also has a Web Filter, SecureAplus doesn't.
SecureAplus is also good. No nags. Freemium includes 1 year of protection. After that, you either buy or get points to extend your free version. It isn't hard to get points, but for multiple computers it can be cumbersome. Their white-list is also large and doesn't have many false positives (a little more than Avast IMO). The white-list popup is nice. It shows whether the file has been signed and how it rates on VirusTotal.
Scan time doesn't matter to me. The initial scan for SecureAplus is normal. It takes that long because it has to scan all of your files via Universal AV. Once done, scans are fast.
My vote went towards Avast (particularly their Avast Business Basic (free) AV).