It is working very good but it can be more good . I will show a small part of how to optimize this "fox" to burn with a bigger speed. This is simple, you have to navigate to about:config, there you have to promise that you will take care by yourself and after that you should look after network.http.pipelining that is by default false - set it as true; after that you have to set and the property network.http.pipelining.maxrequests with a bigger value, but here yu should be very carefully because that can affect you in other ways and if your computer is not the best, it can affect including the computer speed (processor). So be carefully (in the picture, the number for max requests is to large, ignore it).

I don't know exactly the meaning of this properties but I believe that it is concerning how many requests are running in the same time. With other words, if you made this settings, and you call a page if that page contains pictures/css files/javascript files this will call how many requests it can in the same. This can affect the bandwith that you have

See the following picture regarding this settings: