Well, I have been to mine. Horrendous. It took place in the local council offices. First of all I had to go to a reception desk miles from the disabled parking. I was ignored while people chatted about their social lives at the desk. Finally a G4S receptionist demanded to know why I wasn't in a wheelchair, which seemed strange and inappropriate. Then a G4S minder walked me to the waiting room. It was a longer walk than I usually do in the course of a day. All the names of people attending tribunals that day were listed on a big whiteboard for everyone to see.
There was a judge, a doctor and someone who had experience of being a carer. I was told they were supposed to be independent of the DWP but frankly you could have fooled me. They were more like a fundamantalist wing of the DWP.
The judge, whose fake smile never reached his eyes, did not listen properly to what I was saying, and had not read case law properly, having fundamentally misunderstood the 50 yard test for mobility in relation to chronic pain management, where there are apparently various precedents. He talked over me a lot and did not chair the tribunal well at all, so they overran. (I still don't know what the outcome is as they said they would write to me but the letter hasn't arrived).
The doctor had clearly not read my paperwork properly in advance of the tribunal, labouring under the misapprehension that I had back pain for about 2/3 of the tribunal (I don't have back pain, I have sacroiliac pain that refers to my hip, as it said in all of the 50+ pages of documents I had supplied them with), and his medical knowledge was rather lacking - at one point I had to explain what neuropathic pain was and how this interacted with sacroiliac pain, along with the typical medication approaches taken in pain management clinics to deal with this. Luckily the person who had been a carer chipped in to help - she knew more than him as well. (My husband observed that if he had been any good as a doctor he probably wouldn't be wasting his time serving on tribunal panels. Same went for the judge. That guy was never going to make silk, that was for sure).
Finally the carer person managed to patronise me at one stage and upset me to the point of tears at another (at one point in the tribunal I fell apart and I have to say came very close to walking out). Then a representative from the DWP chipped in reeling off various adaptations suitable for people with bad wrists, etc, giving away that she had not read the paperwork properly, as I don't have anything wrong with my wrists. Then when I told her this she said on bad days I should be cooking by sitting on a perching stool whilst simultaneously managing crutches and a hot grill pan. This was a bizarre notion and would be completely impossible to carry out safely in practice. The crowing glory was when she suggested buying an adapted car (£15K?) and installing a stair lift in my house, which because of our set up at home would cost north of £5k, money I would have to find myself. I've been told to avoid using these things and struggle on in order to maintain a decent level of CV fitness, but this person knew it all better and was obsessed with all these adaptations and aids I ought to be using, aids which would cost more than a year's salary after tax and commuting/childcare costs to put in.
I am pretty tough but having to explain the entire history of my disability issues, along with accounting for every single decision I had taken regarding my care along the way, really got to me and the best description was that I left feeling mentally raped/mugged.
My advice to anyone on here would be to take a specialist lawyer in with you (I had consulted with CAB but they did not really make all of the process clear enough, with hindsight).