This is a very general query and will certainly differ from person to person (and test to test !). Whether you are scoring correctly and whether it is ok for GMAT is probably a wrong question since you are comparing paper tests to CAT. Remember that a correct question will be followed by a more difficult question !. Therefore what is important is not the absolute % that is coming out of a paper test, but the absolute accuracy level given ANY question. If the latter is 70% , I am not too sure it will lead to your aim of 700 ! Tough words probably, but you asked for an honest opinion.
If I am through with OG, PP tests are gone. I would rather get hold of the Kaplan
CD (2004) and try to gauge readiness by doing the CAT's therein (4 are there) and also the preparatory tests which are all in CAT format. I know that Kaplan
also sells a pack of 3 CD's (GMAT, LSAT and GRE) and that is more than enough stuff to last three months and to do a heck of a preparation.
Best of Luck !