OG Ed. 12 Level of difficulty

Hello BTG community,

I am currently rallying through the OG Ed. 12th and find that the questions keep getting more difficult.
Is it a plausible inference to assume that the level of difficulty increases and that the last 5-10 questions of each section are representative of a 700+ level?

In regard to the additional OGs for Verbal and Quant books, do the same assumptions apply?

Thanks.

Regards,
Vince