Lee,
May I suggest that you hold off on your upgrade until next week? My own sources are corroborating the rumor that we'll see the "Threshold 2" (aka "Fall Refresh") update next Tuesday. I run several versions of W10 in my various devices (from multiple test devices to production machines), and while I find that my own installs of W10 are serviceable, most folks know that the version of W10 out today was not the one that they wanted as the initial full release version. The Fall Refresh version should bring you to a version that incorporates all the improvements we've seen in the many MS Insider releases and sort of represents what most who know feel is the "real" Windows 10 initial release.
I don't think you'll run into any major issues if you upgrade from Win 8.x to Win10 this week, but most of the updates I've seen in the MS Insider process are quite large and can take from 20 - 40 minutes (feels like hours, LOL.) Anyway, if for no other reason than to save you the ordeal of a large update process twice within a week (?), I might suggest just waiting until the Fall Refresh is published. Again, I am told by reliable sources that this will become available next Tuesday (not sure if it will be AM or PM) or Wednesday...
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[Edit]: Tom (and other Lenovo users),
I am seeing much better results with the very latest W10 installs on several of my Lenovo devices. Note that I only use the ThinkPad line and those are business class, so my results may be different if someone is using a consumer grade device. One of the issues is drivers, and in many cases Lenovo includes some specific services (with resultant modified drivers) to provide things that long time users hold near and dear. (Some of them are not so desired by this community, perhaps.) In any case, the Lenovo (and a few others) situation has been steadily improving in the past few weeks and I would expect it to be pretty smooth with the Fall Refresh release. I will, of course, be putting our own devices through the process and report my findings. I hope this might save some of you some effort.
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Just my 2¢ and meant to be helpful.
-Randall Garrett-
+Apex Software+
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