The litmus test for me is how the account manager assists during account opening. The very best will sit down with you and learn about your business, its financial requirements and ask for your documentation. They will then meet you a second time with the filled in forms and show you where to sign to set everything up.
Banks with the above process generally tend to be much more responsive once your set up, with reps that tend to be much more organised and knowledgable of their banks products.
On the tech side, its important to note that for corporate accounts the main problem you will have is edge cases during processing (Incoming / Outgoing remittance problems). Ironically fancy new i-banking systems tend to fare worse with edge cases. The older, horrible-looking i-banking portals usually have things like audit trails etc that can assist you in times of need. They also load quicker (even if you cant press back without triggering an error)!
Chase worked great
Boa - liars