Here's the deal.
We just returned from a week at WDW (June 7 to 14), on DDxDP. We ate at many signature restaurants, as we always do, including Jiko. We get wine, appetizers, entrees, and desserts.
What we noticed this trip was that EVERY restaurant, including Jiko, has it down pat so that your meals are really not as leisurely as you might like them to be. Whereas in the past we could count on signature dining to take at LEAST two hours, we never were at the table more than 90 minutes this trip. I think the crowds overall and the dining plan have really conspired to make places need to turn their tables quickly. (We had a long conversation with our CM at Yachtsman Steakhouse about this issue.)
So, you can try, but be aware that they work very hard to get you in and out within 90 minutes. You'll be asked for your drink AND appetizer order up front (we'd often have to ask -- honestly -- for time because we wanted to choose wines based on apps and entrees, but then we'd be asked for our full order and never had down time AT ALL between courses).
So these are still wonderful places, Jiko is fantastic (a highlight of our trip, as always), but you'll perhaps want to plan to go somewhere for coffee/drinks afterwards (and/or really work to try to get your meal slowed down) if you want to have an *evening out.*