Just had a play with an Eval Win10 PC at work. Loaded onto a 3 year old laptop with i3 core and 4 gigs of RAM. ( DELL Latitude E5430 )
Seems to run ok and is much more user friendly than Win8 ever was. A lot more Win7 like with decent start menu with extras. They've hidden a lot of the utilities I use, Control Panel for a starter. Given the user just basic access but the search box finds it all if you need it and know what to look for. Even put the Task Bar and system tray back. Nice feature is multiple desktops and the way it handles multiple tasks on-screen a bit more intelligently.
Although it's a 64 bit system it picked up the Win7 32 bit drivers and all the hardware is working and I've detected no lag, quite quick to boot up even.
This must be the 'good' iteration of the OS. Fingers crossed.