Perhaps two years ago I considered Shareaholic (aka sexy bookmarks) to be the #1 social sharing plugin. But not anytime recently. It is buggy, overbloated and overcomplicated, yet somehow lacks almost any customization options.
The most crippling issue is that from time to time the image for one or two of the sharing buttons disappear until wordpress and/or the plugin is updated to the latest version. This is not a 1-time bug, I have noticed it consistently occurring across different wordpress versions and themes, even today when I just updated wordpress on one of my sites (and removed this plugin). If visitors cannot see the sharing button, obviously they're not going to use it. Needless to say, completely unacceptable.
Regarding the plugin itself, there are many different options that have been added over time, like "classic bookmarks" and "related content". The issue with these is there is almost no customization options. You can't even have the "classic" bookmark bar independently from the "sexy bookmarks". At least, I couldn't after half an hour of trying to accomplish this and trying to understand why they would possibly design it they way. What this means is that if you use the "classic" bar, there will still be separate buttons for facebook, twitter, and google+ outside of the classic bar, whether you want it that way or not.
Now for most of my sites I just use a simple and reliable plugin for facebook, G+, and twitter.