I bought it mainly for straight walled pistol calibers, which it is not very accurate at predicting results (it was known for not working well with straight-wall cartridges). I have not upgraded it in a few years, maybe there have been fixes for it, I don't know. Most guys that use it for rifle cartridges say it helps them. It does get me in the ballpark, and once I get a baseline with a real load, I can make adjustments in the program to make better predictions.
IMHO, there will never be a good substitute for starting low and working up. I will take real world results over theoretical predictions any day.