I have an OEM Acer 486. I was lucky as I got it local and for a pretty low price. It works well, but I simply prefer to use my Super Socket 7 Time-machine. It's a Pentium 200, clocked at 133 and with L1 and L2 cache disabled. Gives you ~ a 386DX.
The things are support for larger HDDs, USB which works under Windows 98SE (for copying games or drivers), modern BIOS which you can update to the latest version, great documentation, drivers for W95 and W98, ATX for modern ATX cases and PSU...
I believe the IT industry was a bit like the wild west in the 486 era. With Super Socket 7 there were a lot more standards and quality control I believe. Slot 1 (BX440) is even better, but not as flexible for old games.