My squad has been using the WALK kits but I have ditched the litters for NARP spineboards (they fit in an 1151). In the larger compartment I put a Skedco rope bag and a KED along with massive hemorrage kits in the pockets. I have found that there is no need for anything fancy, if there is a need I have it in my bags.
I previsouly though about the skedco bags but I only had 2 for 4 trucks. The WALKs were pretty easy to aquire