I have to admit something. I am completely in love with this calculator. I hate to sound like a TI fanboy but this thing has saved me a few times on tests already. Even if you're not planning on taking the FE, this is still an all around great calculator.
Normally I'm the type of person to carry around a bulky graphing calculator. However, graphing calculators are not allowed on the FE or PE exams. Also, a fair number of my professors will not allow graphing calculators. On the suggestion of a friend, I looked into what I would eventually decide is the best calculator for the FE exam.
The TI-36X Pro is a solar powered (no LOW BATTERY fear here which helps out a lot when you're stressed and want to bring two calculators in case one dies) scientific calculator that contains unmatched built-in functionality compared to any other scientific calculator I've used. I think every day I discover a new way that it's awesome.
It can do definite integrals. It can do derivatives. It has a ton of built in conversions (imperial to metric, binary to hex, etc.) and can even rapidly switch between complex and polar notation. As an electrical engineer, I can't tell you how useful it is to be able to enter numbers in without converting it back and forth. It's like carrying around a copy of MATLAB in my pocket.
The TI-36X Pro has a built in equation solver function. I mostly use it for quickly solving quadratic equations. If you're looking at solving systems of equations, this next part will amaze you.
Remember the Gauss-Jordan algorithm for solving systems of linear equations? The TI-36X Pro will do that for you.
Doing Gauss-Jordan by hand would take 5 minutes at best, 10 at worst. That's valuable time that you should be doing something else with.
That type of functionality normally comes in high end graphing calculators. Instead you can get it in a Fundamentals of Engineering exam legal scientific calculator.
Go ahead and buy it.