If u want to sue the bank based on negligence, u must have to suffer losses due to their services as you were relying and trusted their professions before the whole incident can become a valid case. <-- I am not a lawyer but this is what i know about negligence..

i had my housing loan with Eon and my car loan with PBB banks and i heard my friends got fixed rate of 3.1% for the 1st two years on their housing loan from PBB..
both of them are so far so good in term of their services