Originally Posted by Zombie Steve
H110 / 296 has a really narrow window it operates well in... that being full power magnum loads. I've heard it described here as a "dragster" powder - throttle is open or it's closed, nothing in between. Normally, start data for H110 is about 1 grain off from max. Not much room to work IMHO. I tend to give up 50-100 or so fps off the top end in magnums using 2400, but I get a lot more flexibility.
Anyway, back to .44 special - you'll have a hard time finding something that performs as well as Unique, particularly with cast loads.
Unique IS a good powder for .44 SPL.