Nigella this is a really old thread..perhaps make a new one and it might get more attention.
Anyway I will note down my experience..
I am on the betablocker Atenolol, have been for 15 years. I take 50mg morning and 25mg at night, I have no side effects and never have had so far. Maximum dose for Atenolol is 100mg so I guess I am on a fairly high dose.
I read on your other post you have been prescribed Bisoprolol at a low dose, you won't know if it suits you until you start it and 1.25mg is a small dose.
What concerns you about taking it?