Hello, JEE is for mainly securing seats in central government institutions like IIT,NIT,IIIT etc.. Nowadays lot of state has also included JEE marks in their state counselling process.IPE is for only getting seats in Andra Pradesh. Though both the exams has the same syllabus JEE will be more problem oriented. You need to work on more sums alongside while learning theory for JEE.Being thorough in your 11 and 12th standard syllabus only is the requirement to ace both the exams.You wont be knowing what preference you may have when you finish your 12th,so it is safer to give JEE and have more options in your hand.

Best of luck.