I don't always retweet, but when I do, I prefer Classic Retweet.
If you use Twitter's standard Web interface, then you have probably grown tired of manually retweeting -- with the cutting, and the pasting, and the typing -- in order to edit or add comment when sharing another's post. With the Classic Retweet extension for Chrome or for Firefox, you get a Tweet window with editable text, helping to streamline the retweeting process.
After installing the extension and refreshing your Twitter page, mouse over a Tweet in your feed and you'll see a "Classic RT" link has been added between the Reply and Retweet links. Clicking on this link opens a new Tweet window with the text of the tweet you aim to retweet, preceded by an RT and the user's Twitter handle. (In contrast, the standard Retweet link calls up a Retweet window where the text is not editable.) Classic Retweet also highlights any characters in red that exceed Twitter's 140-character limit.
(Via AddictiveTips)