It depends on what you want to do with it.
XSLT however is very hard to learn and to read but for some operations it still rocks. Its fast and not depended on the client on how and when some things are rendered.
If you want to do some counting in views for example I found it easier and better performance to use XSLT. For example you want only totals returned for a certain category.
When using XSLT you do the serverside processing and only return to information you want to show. Using JSLink it would require getting all information to the client and do some clientside processing.
However doing some nice ui goodness like transforming fields into nice slides etc i think JSLink is the better choice