AL40s Anyone?

Hey everyone!
I am a new convert to side mount and have greatly enjoyed my first few dives. Being a recreational diver I am generally limited most during a dive by other people's air consumption and thus want to dive with the standard 80cf of air when on rec dive trips. The majority of divers I dive with rent their equipment and are given vest bcds with BM AL80s.
Since I switched to SM for comfort ( amongst the many other benefits) I especially enjoyed SM AL40s when taking my rec SM training. They are easy enough to come by if your area has a shop catering to tec divers and and available to rent. However, currently I have been diving a single SM AL80 as that's what is given to me on all dive boats.
All of this being said what are your thoughts on SM AL40s? A great way to enjoy a rec dive, or to much work compared to SM AL80s?

Points to consider
-2 x AL40s has a true 80 cf vs 77 cf air of the standard AL80
-AL40s are perfectly balanced every dive vs AL80 single tank diving or planning how to divide 3 AL80s on a 3 dive (tank ) day while SM them
-AL40s are slimmer and comfortable while diving
- Down Side is a little extra planning and communication with dive companies. Where I would have to rent from company A and dive with company B

Looking forward to your thoughts
May the 4th be with you!

If a diver has the discipline to use the proper gas management and communicate to a dive buddy the particulars of the set up I see nothing wrong with doing this. It would be like diving with practically nothing on and I myself intend to give it a try this season.

I have used Al40's on quite a few shallow dives.
All shore dives, hauling them around is a breeze.

I do not find them any more difficult than 80's.

I van foresee a logistics concern on a regular 2 tank dive boat trip. You and the crew having to store 4 small tanks vs 2 regular 80's.

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Interesting option indeed. I'm curious how it goes when you try to bring four bottles on a "2 tank trip". Probably not an issue on a small vessel, but I wonder if the bigger boats will raise an eyebrow.

Steel lp45s are dreamy to dive too and hold a lot more gas when properly filled.

rjack321:

Steel lp45s are dreamy to dive too and hold a lot more gas when properly filled.

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..............and they have the added benefit of the weight of two boat anchors.

kelemvor:

Interesting option indeed. I'm curious how it goes when you try to bring four bottles on a "2 tank trip". Probably not an issue on a small vessel, but I wonder if the bigger boats will raise an eyebrow.

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I have not been in this situation YET (it's coming up fast though) but I did read on another thread that what some people do is bring three tanks. On the first dive they breath one down more than the other, then swap the low tank for a full one the second dive.

more math than I want to right now, but a third tank like an HP100 or an HP80 and a transfill whip, and you are diving again with those "little bottles" at near full charge for dive #2.....

I'm in sidemount AL40s from shore here in socal (I own one set). They get floaty towards the end of the dive, and the local fillshops count filling them up with air as 2 fills.. I wish they did by cuft here. Dive boats count is as 'a dive' so I'm good there.

But that's just about the only drawback I can see. Having redundancy in air is never a bad idea if there's no drawbacks to setting yourself up with it. The only other better dive setup I've had buddies talk about is sidemount 60-somethings. Buddy loses gas? Here's a tank

rhwestfall:

more math than I want to right now, but a third tank like an HP100 or an HP80 and a transfill whip, and you are diving again with those "little bottles" at near full charge for dive #2.....

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Hey...What a great idea!
Cheaper than buying more tanks.