As a practical example I can tell you it is worthwhile. I have Windows 10 32-bit running on my faithful Latitude D620 which has the original Centrino Duo T2300 @ 1.67GHz. 120GB HDD
I upgraded the OS over time from the original XP through Windows 7 to Windows 10. I also made sure even under XP that I had the maximum RAM expansion the D620 can take which is 4Gb.
I've had no issues and the old girl is running happily albeit not quite as slick as a $2000 replacement.As long as you give Windows 10 a decent head of RAM ideally in excess of 2Gb, don't restrict free space on your hard drive for it to use dynamically and avoid opening too many apps at a time everything works pretty well.
You will need to upgrade to windows on a like for like basis. For example if you have Home addition 7 then it won't be a free upgrade to windows 10 pro (Only 10 home) however you can just check on the windows 10 upgrade site if you haven't done so already. 32 to 64 is not an issue if your machine is capable and Microsoft will allow this under the upgrade scenario if you have your current OS product key.
For details go to:
I used the above to upgrade the Dell however for a new build on a project machine I used the excellent guide to "Doing a Completely Clean Install of Windows 10" by Bri the Tech Guy here on Bleeping Computer:-