It's evident that AC has been the preferred choice for those who appear for PCS exams. SO belongs to the BSS (Balochistan Secretariat Services) while AC or BCS EB (Balochistan Civil Servces) are the administrators at District level. ACs are usually posted as Assistant Commissioners or EDO (Revenue). while SOs are posted as Section Officers etc. Section Officers are also posted in districts at managerial posts as ADC etc. But ACs are considered the best option. Both have their own promotional cadre and procedures but ACs are considered to be promoted sooner than SOs. DMG officers are posted as ACs while OMG officers are posted at secretarial positions.
So if one aspires to serve at District level -- in other words, some power lust, perks and privileges -- he opts for AC. But SOs are not inferior than ACs, because SOs have also a very fast ascending career, to Secretarial levels.
And soon there will not be any difference between both services because there has been working on Unified Services which includes both services, and a lot of work has been done on it. It will work like PMS (Provincial Management Services) of Punjab and KPK.

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