security - In Windows 8.1, how to know if Early Launch Anti-Malware (ELAM) will work with the Anti-Virus Program?

When looking up about security in Windows 8 / Windows 8.1. I read here http://technet.microsoft.com/en-gb/windows/dn168167.aspx (Securing the Windows 8 Boot Process) that Early Launch Anti-Malware "can load a Microsoft or non-Microsoft antimalware driver before all non-Microsoft boot drivers and applications" and that ELAM is supported by "several non-Microsoft antimalware apps" as well as Windows Defender.

Some sites for Anvi-virus products say that ELAM is supported, but if you wish to use another anti-virus program, is there a way to see if Early Launch Anti-Malware is supported and will work?

eg: Are supported anti-malware programs listed somewhere? or would something be shown to indicate that ELAM is active once the anti-virus program is installed?

Many thanks