I have an Ultimate CF SL and love it.
I bought it as a Frameset and built it myself and can't fault it.A couple of my fellow CC members have Ultimates and a couple have Aeros and no one has any issues and nothing but good to say!
Not ridden any of them but my suggestion would be to ignore marketing guff. An aero bike will not make you noticeably quicker, your position will. Ride both, play around with the position and see which one you like the feel of on the road. Wheel, tyre and pressure make a huge difference so if you can keep them the same across all the bikes you try.
The Ultimate CL is still an aero design but less harsh riding. Personally I'd go the Ultimate SL a more comfortable all round frame especially if you do a lot of climbing. But as stated above it comes down to personal preference.
That would be a personal choice. Even the riders for team Movistar have a choice between the two as some use the Ultimate while others use the Aeroad. As an example Landa rode the Aeroad while with the team, while Valverde uses the Ultimate.