I finally completed my collection of all six colorways of the Asvine V126 fountain pen. All of them have Asvine medium nibs, and I've been delighted with how well all of them feel in the hand and lay down ink. I'm also mighty happy with the inks that I've paired them with, although the shimmer in the Heart of Gold means that I need to spend more time on maintenance than the others.
I have a Vac 700R, too. The TWSBI feels much more substantial than the V126, but it is also twice the price as well. I'd definitely recommend trying one out, though!