I got my Extra back in 74 and I recall some math questions but I have not really been on the Extra bands ( bottom 25 Khz) very often.
I guess the extra fone bands can be good if you are only interested in rare DX.
My thing has always been CW and rag chewing and for the last 5 years pretty much only interested in SKCC. Not using the Extra segments for any of that activity !
I am not sure if we actually had a QS) yet, hope to find you on 80 or 40M sometime. I am usually on 3550 , 7055, 7114 or 7120 evenings and weekends.
In the winter months I am on 1820 in the evenings.
73 from K8JD, SKCC 1395, Centurion 18, Tribune 12, Band Endorsements; 160, 80, 60, 40, 30M, 20M
Ham radio is real Radio, CW is real Hamming!