GK I understand your stance on this. But you are not a borrower if you use the facility accademically.
However you are being taken for a ride by the Banks, particularly on cash. They charge stupid money for cash handling.
GK, set up your direct debit to settle your card IN FULL on the last day of the settlement period. That way you get zero charges, a bit of credit at zero cost, and what is even more satisfying .....All the other jerks with no discipline pay for all the processing costs.
Use traditional plastic only - best is your own bank's VISA card. That way the settlement is auto on the last day.
Another advantage, is the unique cover you get with UK cards as a UK resident, you can return an unsatisfactory product, and reverse the transaction on the supplier and he can do nothing to stop you. Correspondence to the supplier, copy to VISA .......Job done. They even have to collect the product from your premises.
If I have asked anyone to suck eggs - please forgive me