Hi Sara

Just pick the one ~you~ like best (look and price). Both are (about) technically equal, and big chance that you'll stick the rest of your life with the one (brand) you choose in the beginning.

I started of 15 years ago with the look pedals, progressed to shimano pedals because they were less bulky at that time. I switched to Time (RXS) 2 years ago but didn't like that, so I am back to the Shimano SPD-SL.