JSLint is a very good tool to get a strict style in your whole code.
The only pain is the verbose log, and the command line. A configuration file would be easier to use.
jshint isn't strict enough for me.
For instance, you can write :
if ( condition )
jhint doesn't care.
PureLint is a jslint wrapper. You won't get anything more than JSLint, except :
A smaller trace (it won't trace the "OK" part).
A JSON configuration file (.purelintrc) at the top of your repository.
PureLint keeps purity : the only available configurations are here : JSLint configuration