The drivers would be totally down to your RS232-USB adapter or motherboard RS232 port and not the DMM itself. There should be no reason the proprietary Windows software won't work on 7/8/10 if it has access to a COM port. Worst case is to right click the .exe and set compatibility mode for Windows XP.
However, proprietary software is shit as generally you can't use it with your other instruments easily like you would with proper bench meters using VISA or such.
I'm pretty sure the VC8145 protocol has been reverse engineered already? I found
this link but it doesn't work right now. I'm a little surprised it's not on sigrok already either?
IIRC there is no useful SCPI command/response to the protocol it is purely a passive one way broadcast over serial, much like other handheld multimeters with a PC interface.
If I had one I would reverse the protocol for fun but the price tag is way too much when you can get a real bench meter (used) like a 6.5 digit Keithley 2000/2015 or HP/Agilent 34401A for a $100 more. Don't forget the VC8145 will be pretty much worthless on the second hand market, so perhaps a $150-$200 loss, while the proper 6.5 digit bench meter will retain its value and indeed could be sold at a small profit!
(I would go for the Keithley as it works with RS232 - the 34401A needs a pricey GPIB adaptor)