Stumbleupon Button or Addthis Toolbar

Just want to make my website to incorporate social book marking features. For performing this task i tried to put buttons from different providers like Stumbleupon and reddit and others but i just saw a service called addthis and this toolbar is giving much more than Stumbleupon and if we just paste the code of addthis button it will have many toolbars in it. Can some body tell if using individual buttons from different services is better than using a single button which have all of them.
Only comment if you are good at this and have actually experimented with Stumbleupon and really know this stuff.
Both options you have mentioned here are good and it all depends which one is more suitable for you and looks better on the website in question. If you want to save the space then obviously addthis toolbar or any other toolbar like it can solve your purpose. If you are looking to put toolbar for just stumbleupon or any other network like this then you would have to put code for each of them separately which means more graphics and calls while at loading time which could also effect you speed but it may look more beautiful on websites and may mean more visibility in some cases too.