It makes very little difference.
A lot depends on your business, the turnover, whether you need only CHF accounts or also accounts in FX.
Once you make enough, you can begin to negotiate with the bank on fees.
If it is a smallish biz, less than Chf 1mio turnover, i should try using your Cantonal banmk as they are usualy cheapest and may have some offers for you if the biz is in same canton.
Lunches from cantonal banks are usualy better than CS or UBS too