Manually updating microsoft security essentials

I am about to ditch Mc Afee here in a close future, and want to try out MSE.

My question is, is it true that in order for the MSE virus/malware definitions to be updated automatically, does the Windows Update setting have to be set as Install Windows Updates Automatically?

The problem is that some computers may not have stable or regular internet connections to download files that can range from as little as 1MB to over 50MB.I want to research these updates before I do install them.So in order for MSE to update malware definition files Automatically, does Windows Updates have to be set to Install Windows Updates automatically?Whether or not you can automatically install MSE signature updates without automatically running an MSE scan, I am not sure. If I remember correctly when I installed MSE back in 2010 it's been auto updating since then.I may have forgotten but I think it created a scheduled task on its own when installed.