I am a bit late to write this post. Better late than never :)
Why should you consider WSO2 ESB ?
The recently published article will unveil the answer to the question What is WSO2 ESB?
WSO2 ESB is one of the most matured products in the WSO2 stack, it's scalable, it's fast and it has all the features which will support all your integration needs. This i believe is evident and would be self explanatory if you download it.