Although, as the article mentions, TSB are owned by a Spanish bank, Sabadell, and it was the move to Sabadell's platform, developed in Spain, that caused the trouble!
Well before the system migration they rented their online services from LLoyds, and it it was great. Also if you go into a TSB branch they're really good. So until now, I've been happy.
I have a lot of sympathy for TSB's branch staff right now. Previously I'd say they had a good reputation compared to a lot of other high street banks here, but right now they're on the front line dealing with customers who are suffering due to a catastrophic failure, and in reality there is probably very little they can say or do to help. Presumably some of those customers are very angry by now and some of them won't be very polite about it, but it's not the front-line staff's fault this happened any more than it's that customer's.
I'm sure there are plenty of people waiting to do just that.