I think roughly 40% of the remaining code implements the last 20% of the features, and the other 50% is just random bloat.
Request has a lot of extra code to deal with the global state. It's written as one giant class that sets all of its properties on itself (e.g. this.method = options.method, etc., etc., followed by "http.request this"). Further, when it handles HTTP redirects, rather than instantiate a new instance of itself or something it just calls its init method a second time and has to make sure that it resets all of its properties to their default state (e.g. this.method = 'GET'). This is where most of the bugs come in, as well as most of the bloat.
In contrast, our's is a method that calls itself again with new options based on the context when it needs to handle HTTP redirects so we don't need to worry about that sort of stuff.
Request has a lot of extra code to deal with the global state. It's written as one giant class that sets all of its properties on itself (e.g. this.method = options.method, etc., etc., followed by "http.request this"). Further, when it handles HTTP redirects, rather than instantiate a new instance of itself or something it just calls its init method a second time and has to make sure that it resets all of its properties to their default state (e.g. this.method = 'GET'). This is where most of the bugs come in, as well as most of the bloat.
In contrast, our's is a method that calls itself again with new options based on the context when it needs to handle HTTP redirects so we don't need to worry about that sort of stuff.