I still own all of my Whites machines, starting with the free 5900, hence my member name. The V3I was my first ever paid for detector and I used that religiously from 2010 to 2016. Then I went over to the dark side, FBS, with new friends with those machines. It still says that I learned the V3i more seriously than any metal detector after I began metal detector.
Every time I grab my V3i for a specific reason these days, or for fun testing, it amazes me how good it analyzes targets, using the polar display. Working with the detectors following it, makes me appreciate the V3i more.
It is understandable being concerned about support after Whites Electronics went down. That was a disappointing event. I would still buy one now, if it was a "good" seller and priced low, and looked good. It would be nice to get new, recent reports about the left over service centers for Whites, and the real world experiences from service events. My V3i is still solid today. Btw, the DFX and MXT coils won't really work on the V3. They aren't nulled for 3 frequencies.
Good luck! I still love my old V3i and it amazes me if I take it out for a spin ;-)