No doubt about it - I prefer SRAM. I prefer how it looks. Big, splashy graphics. I prefer how it performs. I like that it's an American company, or that at least it's designed here.
Which is funny, because I have Ultegra on two of my bikes, and SRAM Force on only one. It's just tough finding SRAM builds.
I've ridden SRAM Apex before, and I must admit that when shifting on the front chainrings I had to cross my fingers that they wouldn't overshift. It just never really worked that well. I believe they've improved since then with all the trickle down tech. Regardless, even on the Apex, I liked the solid and clear "click!" of the shifters, and the ergonomics.
There's nothing wrong with my Ultegra set ups, but they just kinda feel spongy to me vs the distinct action of SRAM. I've never had an issue with the shifting on the Force. They also don't feel as good to hold shape-wise.
Anyway, I think part of that is simply being creatures of habit as well.