I don't know. For my money vanguard is the worst item in the game. It's over 2000 gold, gives you pretty much nothing over its components, and falls off horribly beyond 20 minutes. For an antimage that's worried about fighting early, you would almost always be better off getting a poor man's shield into a naked vitality booster and ring of regen. With that you get +6 agility, almost the same block, the same +HP, the same +regen, and you can use the ring of regen/vitality booster for your heart and battlefury, making them both happen around 1000 gold faster.
Even a hero like Axe, which you would think would be a perfect vanguard carrier, is better off just getting a mek for his team or going for a bloodstone. Make it so you can disassemble the thing and it would become a lot more relevant.