Not sure if this will help anyone but a couple of weeks ago I switched from Virgins AV to Microsoft Security Essentials.
My connection speed promptly went through the floor.
Everything buffered, sites loaded slowly and at one point the AV itself couldn't update because it couldn't connect.
I think Masque runs MSE (which is why I thought I'd give it a go) so presumably this may not be a problem for everyone. Indeed, it may be just me!
Whatever, I thought mentioning it might save someone from pulling their hair out

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