曾經做過上述某銀行SS. The profit margin in this sector is very slim, annual profit is just ~10 million HKD. 

Progression depends on your role (i.e. FO, MO, BO, client of the bank), it's a custodian bank so the pay is decent, but you will never get bonuses like IBD. People usually go for SS because of its work-life balance, you can expect the whole office to be empty by 7pm.