It appears Apple is pushing El Capitan, but there are some pretty negative reviews.
It is more important to check if El Capitan supports the applications you are using and your hardware is wrking, scanners, printers, audio interfaces, etc. I would hasitate to upgrade, if it meant to upgrade expensive applications as well.
El Capitan added security features, that some users do not like. It is no longer possible to modify the system applications, for example to modify the icon of your mail application. This is to prevent malware from installing itself in your applications folder.
I find El Capitan faster and more responsive than Yosemite.