1) If your PC is NATIVE (PC shipped with Win10 installed) Windows 10 - You can use Windows Native Bluetooth driver, and use the dongle Plug and Play, NO NEED to download the driver! So DG40SA is your better choice with $11.99. Certainly you can choose DG40S with $12.99.
2) If your PC is Windows 7/8/XP / Win 7 / upgraded Win 10 - DG40S is your only choice. You need to download the latest DG40s software / Driver / Program from the CD in the box. Or you can also download the latest driver from here -
|Support System||PC with Win 10, 8, 7, Vista, XP||PC with NATIVE Win 10|
1)Native Win 10 - Plug-n-Play
2)Others - use BlueSoleil
|Work with||Bluetooth headphones / speakers / keyboard / mouse / phones, etc.||Bluetooth headphones / speakers / keyboard / mouse / phones, etc.|