Hi John,
Here's what I do on my rec diving regulator setup.
1 Apecs ATX100 1st stage (yoke)
1 Apecs ATX100 2nd stage (Primary + donor reg)
1 Apecs ATX100 2nd stage (Secondary on bungy around neck)
1 mares analog console (SPG / depth)
1 low pressure inflator whip for BC
I will add/remove my drysuit inflator hose when needed. This usualy stays on my argon bottle regulator though.
The Atomic reg should be fine but consider a high quality, extra 2nd stage as an octo.
I use identical 2nds because I don't want any loss of air delivery capability if I need to donate my primary as this is very likely when I'll need it the most...
Oh, one more point about the integrated BC inflator that I havn't seen anyone else mention. What if your BC has a problem and you need to rent/borrow while it's being serviced? What do you do for an octo then?
With the setup above, I can use it on any standard BC or single tank backplate rig without having to make any sacrifices or changes so I always KNOW where everything is without having to think about it.
I use wrist mounted computers and/or timers without any air integration. Air integration becomes more limited in usefullness when you get to the point that you are switching breathing gasses during the dive. Integrated computers can only monitor 1 gas for now. I'm curious to see when they come up with a multi gas computer with muliple transmitters (1 for each tank...
)
While I don't own a vytec personaly, I think the Vytec wristmount with transmitter is better than the hosemount in that you can see the data without having to fumble around for the console but worse in that the transmitter becomes a point of failure. The upside is that it will continue to calculate the dive profile even if the transmitter quits on you. I would have an analog SPG somewhere on my rig as a backup if I did use the transmitter though.
With practice and as your skills improve, you should generaly know roughly how much gas you have in your tank throughout your dive. Yes, early on you will probably look at your guage very often just to doublecheck... I know I did that a lot early on.
As you dive more, you will find that you look at the guage to confirm what you already know rather to find out "unknown" information. At that point, if the guage reads much lower than expected, it's a sign that you may have a problem and you need to find out what it is or call the dive if you and/or your budy can't figure out what's up quickly and safely.
Hmmm... I'll stop here before I get totaly off track with this post.