Installation: Upgrade of custom. Plus should I 1909 ver?

I'm installing (Pro 64b) but have my W10 HDD from old system in the new build. Thinking it would overwrite (I have a backup). I think a "fresh install" is best, but it is asking if I want to 'Upgrade' or 'Custom' install. Says Upgrade will copy my files, appls, etc.

It would be nice to just switch the key and anything else w/ recognize the new hardware but I think if this acts like an "Upgrade install" from W7 or W8 that I won't get as clean a set of W10 files written.

Which should I choose? Also, will I get to choose between build 1903 and 1909, released a few days ago? Is 1909 AOK? I believe only optional kbs are to worry about.


Thanks,

Mac

Oops, must have read that wrong. Well can anyone tell me what the downside is to doing the 'Reinstall' where it overwrites my W10 files? There are no W7 or 8 files on this HDD, just a previous W10 from my old system.

It sounds like it writes the same files as a fresh install, recognizes new hardware and takes my new key. Haven't read of any issues that would create. Or could create.

Thanks.

If you are booting from the USB flash drive, the upgrade option will not work. Try it, you'll get an error.