What is the difference between くらい～はない & ほど～はない?

Question

• リーさんぐらい動物好きな人はいない。
• リーさんほど動物好きな人はいない。

What is the difference between these two sentences.

Answer 1

In this specific case, the two sentences are interchangeable and there is almost no difference in meaning.

But that does not mean くらい/ぐらい/ほど are always interchangeable. For more generic discussion, see the following questions:

• The difference between くらい and ほど in hyperbole
• What is the difference between 「ほど」 (hodo) and 「ぐらい」 (gurai)?