i practiced with EK101 for the august '06 test...started out with 8's on the first three or four tests..went up to 9's and then 10s...and i got a 9 on the real thing. so...overall, i didn't see a really great improvement...still, i thought that even though the EK passages are easy to read, their answer choices definitely make u think and pay attention to what the overall tone/idea of the passage is. a lot of times, i would get it down to 2 choices and then get stuck...and sumtimes pick the wrong one. i think the key with the EK 101 book is to go back and spend a decent amount of time going over ur answers (wrong and right). what i did was...after grading each test, i would go back to each passage and think thru why i picked that answer (right or wrong) and then read the explanation at the back of the book. i think that helps more than just reading the explanations. i did that for each and every passage even if i got all the questions right. i think that if you spend time reviewing ur answers, u'll definitely see improvement in ur score.
i also used kaplan verbals in the beginning...just because their passages are longer and more boring to read than the EK 101 passages. altho, their questions suck...they r waay too detail oriented.
anyways, i hope this helps and i'm sure with practice u'll do just fine! good luck studyin!