Best Verbal CATs. Which test pack to buy for verbal.

It is good. But the best tests are the ones provided by GMAC. Nothing beats the original content. You can supplement your practice by taking either Veritas/Mgmat practice tests as well. All the best!

Go for the official GMAT prep if possible.

Hi Ayushjoshi07,

Since the Official Scoring algorithm is proprietary, no GMAT company has an exact match for it, thus CAT scores can vary a bit based on the 'biases' involved in their respective designs. The most realistic CATs available are the 6 from GMAC (the 2 free CATs, and each of the 2 that come with Exam Pack 1 and Exam Pack 2), so it would be useful to know how you performed on one of those CATS. Have you taken a FULL-LENGTH CAT yet (with the Essay and IR sections)? If you have, then how did you score? If you have not, then you should plan to take one soon (perhaps this weekend) - and once you have that score, you should post back here, so we can discuss how to adjust your study plans.

GMAT assassins aren't born, they're made,
Rich

official GMAT prep material is the best.please visit MBA.com.

There are two fundatmentals that define a good CAT,
1. the algorithm
2. the question bank.
While, we all can compromise on the first one, the second one is very important. I considered some CAT during my preparation, and here are my take on their verbal section:
1. Kaplan CAT: The questions are superb, but at times very difficult, specially their RC question. But, they will force you to think in the right direction....you can check some of them out here with GMATCLUB tag feature. The bad part is that Kaplan, at time, overestimates your scores. So, don't get too much carried away with your Kaplan scores. Additionally, most Kaplan SC questions generally rely on a single split, while I have seen that all official questions have more than one split.
2. MGMAT CAT: You can rely on their product blindly. Their product are the "standards" in GMAT Prep world.
3. Princeton review CAT: The algorithm gives too much important on the first 10/15 questions, and 1/2 incorrect severely penalizes you and the algorithm does not even consider giving you problems "+5/6" difficulty range. But, from ESR, it can be inferred that the first 10/15 is important in original GMAT too. The second set of question reaches "medium high" only when you have 80%+ accuracy in your fist "medium" set of questions.
Their question bank is also good, and some problems are really well written, specially their RC. But you have to struggle a lot to reach that "good" level questions.
4. Veritas CAT: Some SC questions are really problematic, and need to be fixed.
You may find their SC questions more difficult because of "false split". I cannot comment much on their RC and CR questions, because I only took one free CAT, in which I scored V35.
5. Official CAT: I do not have the necessary qualification to comment on this. Whatever you do, how many of the "above ones" you consider - but do consider the 4/6 official CAT available at MBA.com.