Natural Talent & Vampirism

So I've noticed there are a number of high elo and pro players going down the Ferocity Tree, who have been taking a single point in Vampirism with 4 into Natural Talent on a number of champions. Fiora seems to be the one I'm seeing most.

Now I've noticed when they do this they're typically running a lifesteal quint, and take Doran's Blade into lane, so this'll be basically 5% lifesteal to start the game. Does this make a large difference for the laning phase or would it simply come down to personal preference? I feel like 5% lifesteal at the beginning of the game is rather negligible, but at the same time it could provide a good bit of sustain for trades, especially in combination with her passive & feast as well.

What do you guys think? I'd like to learn Fiora so I'm trying to get some input from a bunch of people before I decide which path to test first.