First of all, I'd take a low-cost Llorente.
But here are my concerns:
Llorente is average at best when it comes to finishing with his feet and playing football on the ground. When it comes to headers, he's a beast, I'll admit to that. But Conte doesn't play football in a way which would exploit this great skill of his. We put in few crosses per match, and when we do, most of them don't even reach their intended target. We have no natural crossers in our team, which would hurt Llorente's game.
Still, we're not likely to sign any "top player" any time soon, so if he can come on a bosman (or on the cheap in January), then sign him up. It would constitute a low-risk, and would be worth to try at the very least.