Very friendly big warning from me. Make sure you run the latest version before upgrading to Windows 10.
I'm using Eset myself and ran into a huge problem today.
I was sure I was running the latest version because it updates itself by apparently not.
Upgraded to Windows 10 today and everything went smooth until first restart.
I was greeted with BSOD and Windows wasn't able to repair itself.
No matter how many times I restarted I was greeted with the very same BSOD and repair loop.
I thought that after so many failed starts Windows will go to recovery options but no.
I found a solution online to delete one of Eset's file but getting to recovery options was a huge pain.
Luckily I had Windows 10 DVD created from downloaded .iso and using that I was finally able to get to recovery options and command prompt.
Offending file: C:\Windows\System32\drivers\epfwwfp.sys
It took me couple of hours to sort it out.
I hope I'll save someone's bacon by posting this.
Posted here for all.
My general suggestion to all, regardless what AV program you may be using...would be to try to ensure that you have the most current version of such software installed...before attempting to do the upgrade install of Win 10.