you don’t want to have “update packs” that are not from the original source. Period.
I’d suggest to have a look at the c’t offline update tool, (download site), which gets the updates directly from MS servers and allows you to create a CD/DVD that installs all updates without an internet connection. You may also integrate these updates into your install CD using Nlite.
Unfortunately I am in the US not UK as the link goes. The link there goes to M$ but only to download SP3 not how to integrate Post-SP3 release. I don’t see anything wrong with using Rynvanm update pack. Unless someone can give proof otherwise?? What I am doing is to update my SP3 iso update media so it has the latest releases. I already can do SP3 slipstream but that doesn’t contain all the latest release so I combined it with Rynvanm post-SP3 to bring it up to current.