I just booked BOS-CDG one-way in J on Delta using VS Flying club miles for the summer of 2018. It was 50,000 FlyingClub Miles per seat and $5.60 in tax. I was able to find a unicorn: 4 J seats all on the same flight for a Friday evening departure.
The experience could not have been easier. I found the seats on Delta.com and verified they were available for partners with FlyingBlue. I called up VS and the agent confirmed availability instantly. I was about 6,000 miles short in my account and transferred those from a credit card whilst the agent was on the phone. The entire process including giving all of the names and DOBs was less than 10 minutes including hold time. Confirmation email came through within a minute and I was able to select seats on delta.com.
People complain about VS miles, I have had some of by best value redemptions with them.