Having ridden both bents and DFs in the rain I'd rather be riding a DF. Jackets work better in the sitting bent forward position on a DF than the reclined position on a bent. You can also use something like rain legs effectively on a DF which are nice when riding hard and not wanting to get super sweaty.
Having said that you can figure out ways to be comfortable on a bent in the rain. It will take some trial and error though.