So the question is, what should I pick. Getting two Y r/t tickets, perfect dates AND Saver/ Low awards on both VS and DL.

Delta is charging 60,000 miles + ~$200 in fees, each, while VS for almost the same flights is coming out to be 35,000 miles +~$450 in fees.

Now I was quite surprised to see NYC-LHR at 35,000 miles (I am assuming this is round trip, nowhere on the page does it say its one way) in the first place, but now the kicker is the current AMEX promo that gives an additional 30% bonus for all VS transfers! So this NYC-LON flight is going to be in the region of 25,000 miles + the 450 bucks, each.

What does the collective FT wisdom say? Spend the extra miles on DL and save the 250 bucks (x 2) or spend the extra money and go for the VS deal that is approximately 70,000 points cheaper but an additional 500 dollars?

Many thanks in advance!