We got both tops when we ordered ours- back in the day, it was the only way to order your Jeep. However, the soft tops have come A LONG way in terms of being quiet- to the degree that I could deal with only the soft top. However, in traffic, it is a huge noise difference, and the AC has to work a lot harder to keep up. Also, putting stuff in the back is a lot harder with the soft top. I really wish you could roll the window up like you used to be able to with the YJ and I think the TJ.
Something I'd recommend on the top deal is one of those Spiderweb Shades. We got one so we could go topless with the baby and it rocks. Getting the hard top on with it there is a real PITA, but still worth it.