I use an H style harness on my Lionhead. You really have to know your rabbit and decide if it’s a good idea to use a harness. I know for certain that my seven-year-old Lionhead isn’t going to run off. The harness is only there as an extra precaution. However, if I were to put it on one of my Netherland dwarfs, they would certainly get hurt. If your rabbit is calm and you decide a harness is a good fit, I would definitely recommend an H style cat harness.
A harness is only a part of the equation. [As others have noted, the h-style is the only type recommended-- at least for those rabbits that are receptive to a harness. Other harness types can be extremely dangerous.]
Aside from harness choice, there are some reasons for and methods of bringing a rabbit outdoors that come with great risk. There are wrong (unsafe) ways and recommended (safe) ways. Take a look at the following page for a more thorough review of things to consider before choosing to use a harness.