The arguments between Ryan and Hart were interesting, particularly about Kilmichael and the aftermath.I think it's good to read all three books.
Tom Barry's book is actually a good description of guerrilla warfare, even if he does big up his own role (well he would, wouldn't he?) and some of his tales don't ring true, or at least are a bit embellished.
Hart's book is excellent, except oddly enough when it comes to Kilmichael, when it descends into overt partisanship and is frankly nonsense at times, it's odd that such a good book should be most recalled for its weakest chapter.
Meda Ryan is fun, like a night in a pub singing all the old rebel songs for the crack, sometimes it's just good for a laugh to read old, unreconstructed, unrevised Irish history, while realising that a lot of it is bollocks but still entertaining.
Read all three and form your own judgement.