SBI is renowned bank in public sector. It has number of branches & Atm in india. It is the first Indian bank who open their branch in aboard( Frankfurt, Germany), plus it also provide their services via kiosk, by which you can do banking in weekend also. It have very large & wide network in India, you can easily find its ATM anywhere.
Their offline service is nice, By the green channel counter you can instant submit or withdraw fund. Im very much impressed with their online net banking service very secure & easy to use, able to transfer fund, make bill payments, get intimation by SMS on every transactions & their mobile banking App revolutionary step to make banking very fast & innovative.
Might be possible youll get frustrated with some of the employees behaviour or assistance in SBI but except this in terms of quality, reliability & service it is the best bank in india.