Well, it's only a +1/+0 buff; really the Lifelink is the greater benefit. It's important to remember that just because Sorin cast a spell quickly and over a wide area doesn't mean that it's a weak spell. He's been practicing magic for over six-thousand years, a touch longer than Archer's been at it. Do what thou wilt, though, it's up to you if you want the buff I guess.