DIR is not brand specific, however there are obviously some brands that address our concerns better than others.... you know the players.
As for drysuits, DIR concerns are:
- Range of motion in undergarment and suit (reaching valves)
- Good cut for men *and women* (no excess material to create more drag and/or complicate buoyancy)
- Simplistic inflation, deflation and zipper systems
- Inherant buoyancy of material (means less weight, same reason we don't pad BCs)
- Resistance to compression (for undergarments, a concern if suit floods)
There are always other concerns such as ability to repair quickly, price, ease of traveling with the suit that may come into play, but are not necessary prescribed by the philosophy.
We know that the DUI TLS350 with 400g thinsulate works, so we often put people in that direction since we won't have to troubleshoot whether it's the gear or the diver causing a difficulty. This is not to say that you might not be able to find something else that works.