@Mike1967
forward attachment is the leash that goes from the loop bungee to the chest d-ring or wherever it attaches. Keeps the loop from flopping around when disconnected but also prevents it from falling too low. When you go inverted, the bungee can only come back so far, and the friction from the inflator/regulator hoses tends to keep it in place the rest of the way. I have my tank bands up very high *those are HP120's so rather long*, and the tanks don't want to see saw very much because of that which also helps keep them normal.
No 5th port on that first stage, though I do have swivel turret regs. I never found a situation where the 5th ports did anything for me that were really beneficial. On the long hose side they can help if you're diving dry during an air share, but that was really the only benefit. I dive with a 9ft hose and since I'm cave diving the odds of ever having to donate are low enough that I'll deal with the drysuit hose turning up during a single-file air share. I find the hose routing to be cleaner without using them.
Butterfly clips on the bottom make clipping them in significantly easier. With AL80's it's less beneficial, but remember that these tanks are quite negatively bouyant at the start of the dive and it's a fairly long lever arm. If you ever have to go bottle off, it makes putting them back on much easier. If I was diving with AL80's I'd still probably use them because I like them, but they aren't as critical.
They're not quite in line with the valve stub, there is a bit of clocking but not much. With the regulators that are on there *Poseidon 3960's for reference*, they are quite comfortable in that position. With my MK25's I have to clock it a bit more for comfort.
No butt plate, but I do use drop d-rings mounted as high back on the waist belt as I can with that rig. I don't like normal d-rings because they rotate which allows the tank a good 4" of movement when you roll. These are the same basic design that
@cool_hardware52 came up with for the Razor for the butt pouch attachement, and were actually originally designed as an offset d-ring for use under the counterlungs of a rebreather. They're quite nice and really help to keep the bottom of the tanks in close.
These are LP120's vs HP120's *19 liter vs 15 liter, but the clips are in the same spot. For top attachment, it's really just getting the bungee loop the right length for your body. Most people struggle with that and you end up making the bungees much shorter than you'd think and their attachment to the front of the harness significantly longer.
I'm using transmitters now as well, but haven't really changed anything on the LP side or the orientation as the hoses are routed comfortably so never felt a need to change them. As said above, before those regulators are going to hit something, whatever that something is has to hit your shoulder, chest, and tank so it'll have to be pretty stabby to get inbetween your armpit and the tank