I passed Geotech on my second attempt this time around. In October last year I got 40/80 (23 AM, 17PM) with TX grade of 61% - I took SOPE which I thought was okay for breadth for not at all good for depth. So I switched to EET for depth for the April exam and that is what saved me this time. I passed this time with 76% grade, I believe I did very good on the breadth and fairly okay in the depth. As far as I can remember, more than 50% of the questions were covered directly/ indirectly from EET course, may be 10-15% questions from SOPE, few questions from Geotechnical handbook and 1-2 questions from OSHA book - rest were conceptual questions.
I highly recommend EET for Geotech esp. for the numerical part, lot of conceptual questions were also covered in their binder. Few things that worked for me:
1) You have to absolutely kill the morning section - try to score in excess of 35, I know it sounds high but very doable. 2) 15-20 questions in the Geotech depth will be numerical, try to get most of them to compensate for Geotech conceptual questions - EET should cover all the numerical problems. 3) For Geotech depth conceptual questions - I'd say refer to NCEES syllabus for Geotech and cover each conceptual topic as stated by them. I reviewed EET, SOPE, geotechnical engineer's handbook (by Robert Day), watched numerous youtube videos for basic Geotech concepts. I also bought few books by Das, Holtz, Coduto but never used them.
Let me know if you have any doubts.