What TH White has done is amazing, even if it is a little patchy in parts. A parable of 20th C ideology (and ultimately anarchy) dressed up as a King Arthur story filled with all sorts of cultural references, funny quips, insights into the daily life of the middle/dark ages, and some beautiful writing makes this a classic. It certainly gets better as it goes on. You can see his progression as a writer evolve as the writing gets tighter and the structure better.
If it wasn't for some of the slow and meandering bits, and the overly overt final chapter, I would give it 5 stars.
Also, Neville Jason is a BRILLIANT performer. I am certainly going to pick up more of his stuff.