Once the teething problems had been sorted, T5 represented a huge step forward for those of us using BA regularly. I (briefly) started to enjoy passing through LHR again. However, I am not sure there is much to celebrate now. Even the best bits of T5 (the CCR, for example) have been left behind by the astonishing development of other hub airports. T5 now feels like little more than a larger and more overcrowded version of T4 from all those years ago. The dreaded A10 first thing in the morning, the bus back to T5A late at night, the ludicrously overcrowded GFL (I haven't been up to the business lounge but I hear it is a zoo), more and more shops and promotional stands crammed into every corner (I even had some git interrupt my snooze on the CCR terrace to try and sell me a Samsung phone once) and the tediously infrequent transit all make for a miserable experience. Passing through so many other European, ME, Asian and even some American airports is a dream by comparison.
It was just another woefully thought through piece of substandard British infrastructure that could have been a show piece but which has become little more than a national embarrassment.