What I do know is that all the verbal questions from the paper tests can be found in 1000SC, 1000RC, and 1000CR. As for the math, I don't really know, however, they are pretty much easier compared to the CAT tests. My best advise is to stick to the gmatclub challenges. To take 1 test from the gmat challenge every single day should be more than fine. Then once you finish 1 test for the day and will have reviewed your mistakes, move on to the verbal questions from the 1000 series, by doing 20 questions each. If you do that for 1 month, you will have covered about 600 questions per verbal section. Also, you will have finished the gmatclub challenge because it provides 25 different math tests. I think it's better to do a set of 20 questions each for the verbal because you want to slowly digest any new grammar that you learn from your mistakes. I think it could be hard to remember them when you do a lot more. imagine if you did 50 questions each day and got half of them wrong for each section. imagine how much new stuff you will need to learn every single day for each verbal section? and what are the chances of you remembering what you have learnt when you have such a bulk? not much i guess....
As for PR CAT, its math seems ok but its scoring is soo wrong. you can score 37 on math when you get only 8 mistakes! so don't let the score intimidate you. As for the verbal, i thought it was way too easy.
hope this helps