I decided to remove comment moderation for the blog. I used it mainly to be sure that no spam pass the filter, but after some months of testing I verify that Akismet really does a good work, intercepting all the spam comments.
Moreover I setup the WP-reCAPTCHA plugin to add a CAPTCHA in the end of the post, making life harder for spammers. I really like to have moderation removed, primarily because I have to check it often to be sure that no comment gets lost, moreover I like that readers can immediately see comments in the post. A blog is dead without comments enabled.