For me, though, the whole sandwich nature of the doner is essential. Eating a doner should essentially be a race between your appetite and the structural integrity of the increasingly grease-soaked pitta bread.
I went to a respectable Turkish restaurant that made their own doners and, while the meat was much nicer than your average kebab shop, a pile of it on a plate with rice and pickles and whatnot just isn't as satisfying because it's not a sandwich.