The JF-17 is essentially a modern day version of the mig-21 or f-5 , a cheap lightweight point defense fighter. It has less sophisticated avionics and systems than the Gripen and the radar is also less capable but it is the cheapest fighter on the market today. Its Achilles heel is that it relies on a russian engine that is more maintenance heavy and has a shorter service life than its western equivalents. Once an indigenous engine is fitted I could see export sales take off.

This old article explains some details of the aircraft:

http://elmihiro.blogspot.com/2007/04/pakistans-jf-17-thunder-analysis.html