A few of the posts in this thread concern me. Many of you can't wait to get the latest build, I have no problem with that. But I don't want to see a bunch of posts on the 29th or 3oth about how things aren't working as you expected because of how you installed Windows 10. If you are using the Insider site to get the updates, and that was the first and only way you have done it, you don't have a worry in the world when it comes time for the "final" roll-out. But if you haven't read this thread you may want to refresh your memory. http://www.surfaceforums.net/threads/windows-10-upgrade-warning-concern.15739/
Of course you can always wait until the last minute.
Meh. I've a whole year to sort it out if i need. Not that hard to install an 8.1 recovery image if needs be, and then just upgrade via Update.