Something I prefer about a roller is that it allows the jib to be stored when the need arises. Being that I have a front tramp it allows activities like using the tramp as a tent site or for fishing from on lite wind days.

I used to sail with a battened jib on a sol cat, going to a roller on my second boat did not affect my turning at all. I prefer a jib, I have noted that a timely deployed jib shape makes for significant thrust coming out of a turn. Also on days when it is 15 - 20 and I need a rest or some safe house keeping time, a jib allows me to loose my main free and the cat will sail close and steady without my hand on the tiller.

Can an una rig do that? Plus, jibs bring a certain design beauty to a boat.