You can take a loot at this Q&A about the octane. For your car, I'd say go with whatever the manufacturer says. They say "87+" then 88 will run fine. There are factors other than the octane rating that come into play with the question "which is better..." so I hesitate to get too far into that.
In my personal experience, I have found that I get better fuel economy from "Premium" (91 Octane in California) fuel, but I will also notice a huge difference between the gas company that I decide to use. (NOTE: This is also much more noticeable with my 296cc motorcycle than any var I've done the test with.)
My best advice is to do your study, test each, and choose the one that seems to most benefit you and your vehicle. Running a couple tanks of different gas won't do any harm (as long as it's within the manufacturer's spec - don't use something like diesel or jet fuel!!!), so you can test both and see what your car prefers. :)