Hey

Both the sources are good , it depends on you how you manage your time and how consistent you remain throughout your preparation .

No matter what you choose , trust your choice and read from that source only.

Diving right into the point most say that Marrow is better than DAMS . Because of various reasons .

For preparation in 6 months I would recommend you to solve as many as qbanks  you can , do previous 5 years questions.  Revise notes .

Give importance to important topics and repeated topics

Study for 5-6 hrs daily

Give grand tests monthly or twice a months .

All the best .