Best Vantage users?

Anyone with a high attack and/or distant counter.

why not both

High attack units. Think anyone who you would be terrified to see at low health WITH vantage. QR IMO is better on tanks whether they have high attack or not since they DEFINITELY wont double without it. Both go great on DC users obviously.

A few vantage users I have are Hector, Black Knight, Lyn, Lucina, Ike, and Camus. But for the most part, any heavy damage dealers (base attack with weapon 50+, higher is better) would make excellent use of vantage, unless they have an aching desire for QR, like most slow hard hitting units do.

Units with high atk or strong specials like black knight, Hector
and units with dc and who use fury like ryoma, camus xander ;p

Fae (although i gave her QR2, she works fine with Vantage), Joshua, Hector, Michalis and Lilina

I run a good adult Tiki with vantage and fury, it's quite a lot of fun, but she does need the occaisonally healing