
Brent T. S. answered 07/17/19
I am a teacher/tutor with almost 20 years experience.
There are no cons, other than the fact that such deliberate, methodical approaches to reading take time and energy, and laborly reading like this comes at a cost, but the pay-offs are well-worth the investment.
The pros, then, are in the pay-offs, which are numerous: the SQ3R method (and similar such methods), when practiced patiently and persistently, can and does improve both comprehension (understanding) and retention (memory).
Furthermore, Questioning involves interrogation, which stimulates critical thinking, and critical thinking improves intelligence.
Recitation, moreover, requires the ability to paraphrase an author's ideas and information, using your own words and your own unique word order; i.e., paraphrasing is the ability to use synonyms (words) and syntax (word order) to express ideas and information that are semantically equivalent to the author's.
Finally, the SQ3R method, accordingly, improves one's writing, for good writers are good readers, and good readers use a variety of strategies and techniques to improve their comprehension and retention, including the SQ3R method.