Ever ridden a Heckler? The original was superb and I don't think they've done much to change that. My mate had one, then a bullitt. He's gettin a new Heckler later this year. You need to try it yourself really. There must be a demo somewhere in the country?
I read a good test on MTBR recently Prophet vs Heckler, to cut a very long story short both bikes are very similar, similar geometry single pivot etc, etc... The Hecklers slightly burlier build made it more stable (only very slightly) on big rocky downhills and the Prophet was a tad more flickable & manouverable in tight twisty singletrack and can be built up a shade lighter. So I guess it depends where you get the most fun from, I think they are both great all round, tough, no nonsense full sussers. I've been riding a Prophet for two years and still loving it. Try and see which feels best, where you based?