Review classes for PE Chemical are very few and if you live in Houston, I would recommend Testmasters or Delaware DVD review course. From my experience if you study as per the PE exam specifications, you should be in a good shape to pass. I dont necessarily recommend review course if you have sufficient time on your hands studying and understanding fundamentals.
NCEES sample exam book is very helpful and suggest, you practise the test a month before the exam. Do not open it before then and if you do, you are wasting your time and efforts you put in for preparation because it will help you understand how much you are prepared.
Let me know if you need anything else?