The Gliem includes ALL the questions the test bank I believe. The FAA actually only uses about 700 of the questions on the actual test (they rotate them out periodically).

You want to find a practice test where the vendor has made an effort to identify which 700 questions are currently in use by the FAA...this narrows things down for you a great deal.

ATP flight school has a computer-based training system which does that. You work through the CBT and take the actual test the same day, but you pay 300 bucks.

I heard there is a vendor who sells a software package that has the questions narrowed down also. Don't know the name, but the product info should state that question bank has been narrowed down.