I have never been a major proponent of the IIHS' rear protection rating, sometimes called a "crash test" by the media. In fact, this is a test only of a vehicle seat and is done on a test sled.
First, severe rear impacts are only a small percentage of fatal crashes. Next, no actual vehicle impact test is performed as they do in the frontal and offset tests. So, no evaluation of the vehicle's rear crush space, intrusion or other injury measures is done at all. Furthermore, they don't always evaluate every type of vehicle seat in a given vehicle, and certainly not every type that may appear in other versions of the same vehicle that vary in interior seating choices. Also, they only do their test at a typical setting of the vehicle seat back recline and head restraint height. In that regard, it is quite likely that a safety conscious passenger could adjust these and be much safer that what the test indicates. Likewise, someone who doesn't bother at all could end up less safe if the adjustments are poor. Finally, the rear-protection score does not affect children in 5-point harness seats and high back boosters at all, since their child restraints provide their back, neck and head support.
The IIHS rear protection score is important because whiplash-type injuries occur in the more common rear crashes at lower speeds that are not fatal ones.
All else equal, vehicles with dynamic head restraints have a real safety advantage over other models. On the other hand, I would not sacrifice certain other safety features or frontal and side crash test results in favor of a model with a top rear-protection score, especially if I felt I could get a good adjustment of the vehicle seat and head restraints.
All this said, I think that many of the models the IIHS lists as, "ALSO-RANS" are also top contenders to be among the safest vehicles available. While I do believe that the inclusion of stability control is a good thing, the IIHS awards do not even consider the NHTSA crash test ratings. These ratings are complementary to the IIHS crash test ratings as they test different types of common frontal and side impacts.
Taking the list of "WINNERS" and "ALSO-RANS" from the IIHS news release, I have narrowed it down by taking those models that also received quadruple 5-star NHTSA crash test results. This resulting list really is an exclusive group of models that had designs good enough to get top results in all the frontal and side impact tests done in the USA. Some models (especially luxury makes) included on the IIHS list have not had all the NHTSA tests performed, yet, so those are not included, either. I feel that the following 13 models are just as safe or perhaps even safer than the 13 listed by the IIHS. Note that the first 9 models below appear on both lists.
2007 Vehicles that received top ratings (Good, 5-star) in all IIHS and NHTSA frontal and side impact crash tests and have stability control:
Hyundai Entourage
Kia Sedona
Subaru Legacy (with optional stability control)
Honda Odyssey
Mercedes M-Class
Honda Pilot
Subaru B9 Tribeca (Lacks side curtain airbags in 3rd row)
Nissan Quest
Toyota Camry
Toyota Avalon
Acura RDX
Honda CR-V
Subaru Forester (with optional stability control)
Certainly, there are many models like the Volvo XC90 and Acura TL that just miss this list because they had a single "4-star" or "Acceptable" rating. Others like the Honda Civic, Ford Five Hundred and Freestyle had top scores but lacked stability control. Even these models are among the safest choices on the road. In fact, most models on the first two pages of the Informed For Life risk rating list are very safe vehicles, especially if equipped with stability control and side curtain airbags. Only a few models on the first two pages are questionable, only because they lack many test results. See
http://www.informedforlife.org/demos/FCKeditor/UserFiles/File/2007SCORE.pdf .