I've taken DIR-F, and dive a Hogarthian rig. I dive 100% recreational at this point, with no deco stops or stage bottles. If/when I go more technical, I suspect that I would end up more DIR-like, but for now what I have works.
Where I'm not 100% DIR is:
1) I dive with non-DIR folks, who are pretty scarey in their buddy/safety skills. Thank goodness we stay fairly shallow, but I wouldn't want to dive with these folks on deeper dives.
2) I rot my brain with a computer on every dive. I need to be more aware of my dive environment, but for now I'm working on better buoyancy and buddy skills, so for now, the computer makes me a safer diver by letting my feeble mind focus on those parts of the dive.
3) I'm not in great shape. DIR means a committment to working out 3-5 days/week, and I'm nowhere near there.
4) I Halcyon ACB+ weight pockets. I've tried weight belts, and to be honest, I *really* like my ACB pockets. Others hate it, but I find it works well for me.
5) Dive flag. Unfortunately, carrying a dive flag is mandatory where I dive, as we have boats constantly whizzing around, and I'm shore diving. While this isn't a DIR/non-DIR issue, some people seem to think that in order to be DIR, you have to dive without a flag.
6) Ability to reach my valves. When I dove wet I could do my valves, but ever since I moved to a drysuit, I'm no longer able to access my valves. I've tried and I've tried, but my drysuit binds up as soon as I get 5' underwater, and I'm unable to reach my valves. For now, it's pretty much a non-issue since I dive in fairly shallow water, but if I started doing technical diving, this would become an issue.
7) What I have taken from DIR:
1) Buddy skills. No way would I dive solo intentionally, although many of my 'buddies' essentially make me a solo diver, since they pay no attention. However, I'm working on that aspect.
2) Preparation. Lately, I've been challenging my buddies to be more aware, but allowing me to do 'snap' OAA drills on them. So far it's been more humerous than anything else, but I've got the local PADI instructor concerned about both his own skills, as well as the skill level of his students, so we're making progress.
3) BP/Wings + bungie/long hose. Basically, my rig is configured DIR/Hogarthian style. To be honest, I'm convinced that this style is the wave of the future, while still being the style of the past. It simply works, and is much easier to dive with.
4) Some of the better attitudes. Prior to taking DIR-F, I was much lazier about my trim/buoyancy and buddy skills. After taking the course with my wife, I now try to work on my skills at least once/week (either in the pool or in open water). I realized that to be a better diver meant I had to commit to working on skills. Besides, its still fun, and gives me something more to do other than looking at rocks/mud. ;-)
Hope this helps!
Nate