Eval is needed to para tame them, but even with only GM eval you can get like eight or so taming attempts through the anger cycle, then have someone flash invis on you when you get the start of the taming cycle. Higher the Eval, the longer the paralize. Even get an Evil omen in there before the paralize for it to last a little longer. My fav though has to be using ethral voyage where the anger cycle doens't start till you are out of form.

If youre looking for a special color Cu for looks and riding, the paralyze method isnt that big of a deal, but if you plan on fighting with it, forget paralyzing it.

If I remember rightly, its a 10 or 20% extra drop in stats...possibly skills too. Its just generally regarded as a bad idea