I love Beersmith as well. It could do things better and has some very wierd errors in it, but nothing I can't live with. I should submit them, as submitting bug fix requests is what I do in my day job, but I just don't feel like fighting the system at home after doing it all day.
If you want something to calc recipes and keep track of your inventory and what you brewed, it's pretty cool.
I personally would like to see it do more, and if BTP doesn't do all Beersmith does, then it probably isn't worth it.