While I would have agreed with you when I first bought one of the newer lightweight OR organizers, I can now say that they are actually MORE durable then the original medium weight cordura organizers.
I have used a number of OR organizers for years, mini-survival or E&E kits, repair kits, sub/specialty kits in my medical packs and just as an organizer in larger packs.
I purchased one of the new OR oganizers to try, it was put into service carrying everyday stuff in my wildland pack (batteries, sun block, gum, etc). In this fuction it was handeled and tossed around, opened and closed multiple times a day in a less than optimal enviroment. The pouch remained cleaner then the older ones, as did the contents. The outter fabric showed fewer signes of wear and was more difficult to tear than the older cordura cases. The quality of every OR pouch I have owned has been great, but these are truely an improvment.
As for a first aid kit for your vehicle, there are many many choices out there. And as Doug noted you can't go wrong with anything from Conterra (you can go to
www.lightfighter.net, where my nickname has become "Mr Conterra" to some, and read a review of some conterra packs). Conterra's packs are by far the best medical kits I Have found for off road/remote medicine. They are expensive, and they require you to know what you want to carry before you order (so you can buy the coorisponding organizing products) but a pack like their
Infinity Pro Fanny Pack or
Responder I & II packs would make excelent medium/large first aid kit bags. I used a Infinity Pro fanny pack for years as a First In EMS bag and loved it!
If you are looking for something less expensive, I found the
Country Comm's EOD bag to be a great foundation for a first aid kit Although not brightly colored or marked as a medical pack it is big enough with just enought organization to be the foundation of a good first aid bag. I built up a few of these for a BSA troop locally and used simple plano
Plano Moldings Organizer Boxes to organize the small items (labling the top of the box for east identification). A few dividers had to be cut out for some items, but in the end we had a well organized durable kit. The out side has a velcro strip for a military name strip, so I had a local shop embroider a name strip with TROOP 690 with red cross before and after. All together the total cost of the bag, organizers and name strip was $44. These packs are great because they have PALS webbing and attackment webbing, so they can be attached to a backpack, made into a fanny pack, or whatever fits your needs.