Like Skeet028 Ive not always had the best results with the XTP bullet in 44mag, or the Special for that matter. Not that I have that many 44's but my Redhawk, my 29 and the Henry all seem to better with other bullets.
I believe my best one was 23.5gr of H110 with the 240gr and then 18gr of IMR800X with the 200gr version screams out of the Henrys 20" barrel at 2100fps and is more than accurate enough for me. Seems though that my guns at least all prefer other bullets and will always do better over a wider range of charge weights, powders etc. I will give up on the XTP's and then try them again, maybe some day Ill luck into a good consistent load that my guns seem to like. The XTP is almost always available and priced well most of the time.
Its weird too, my 357's love them with almost any powder and my 454 and 45lc seems to do fine with them too..
Interesting thread though because I still have 5 boxes of .430"'s under the bench that Ive been eyeballing, maybe Ill learn something from your question and the responses.