1) Transfers
While in SSC there are certain posts where candidates are placed only in Delhi. In most of the posts, frequency of transfer is very low. I have discussed about SCC posts in my previous post.
No bank accepts any request to change posting location in first two years of service. So if you have been selected in IBPS PO III, wait to throw party. May be you are living in Delhi and get placed in Kerala. Yes, it is possible. I cracked IBPS PO twice, I am from Ludhiana and once I placed in Mumbai and second time I placed in Bangalore. I didn't join. So if you are really serious about PO then make up your mind to go away from your home-city.
2) Social status
There is no logical reason behind this fact but being an Income Tax Inspector is much better than a Bank PO. Posts in SSC are more respectable and stable.3) No bond
In Bank PO, various banks ask for upto 3 years bond. While there is no such bond in case of SSC posts. In case you get better opportunity or you want to start your own business or you are preparing for UPSC, you don't need to pay even a single penny while leaving the job in SSC.While SSC CGL lots has lots of benefits over IBPS PO but it's relatively difficult to crack SSC CGL than IBPS PO. In IBPS PO there is selection ratio of about 2% whereas in SSC selection ratio is less than 0.5% (After Tier I and Tier II exams).