I’m not sure I understand why keeping the SPG as part of your standard equipment configuration feels cumbersome or a burden of sorts - not like it’s a gigantic grandfather clock one is carrying that upsets one’s weight and buoyancy calculations. It is small and compact enough to tuck in to one side… I use both and often check my SPG immediately after reading the pressure off my transmitter - just to keep my muscle memory and also compare accuracy of each device - typically the SPG reads 3-4 bar more compared to the AI transmitter. Knowing how my devices behave over time and having relative reference data points gives me a feeling of trust about the state of my gear.
On my last dive vacation, I found my Transmitter battery had died and so I used only the SPG the first few days until I got the battery replaced. But the DC had paired with the transmitter on the boat on the 1st day just before the 1st dive, and only when I commenced the dive that I realised I had a non-functional device - perhaps I did not look properly for low battery warnings … anyways while this was the first dive of my vacation with the dive shop, a group of tourists who were instructors in their home country had already been diving a few days with them and so the first dive of that day was a moderately difficult-level (considering tropical warm water conditions) deep channel dive in the Maldives. Needless to say it was a “high effort” dive in terms of navigating strong currents, and staying together with the group, where we took the entire first 10 minutes of the descent to find our way to a suitable spot on the cliffs edge of the channel and deploy our reef hooks. And then practically everyone was low on air at 35 mins into the dive. Having the SPG as a backup device meant I didn’t start excessively worrying or start panicking about having to abort the dive in strong currents during a period everyone was basically fending for themselves while navigating the currents and racing to a safe spot the dive leader was scanning for on the channels ledge. I took delight in the moment I told myself that it didn’t matter - thanks to my backup SPG, I could continue as if nothing had happened. We saw something like 30-40 gray reef sharks swimming around over the channel and ledge, on that dive. Talk about the peace of mind that being suitably prepared brings…
This thread really needs a poll:
Q: Do you use both AI and SPG on your dives?
Option1: No I leave my grandfather-clock sized SPG on the boat
Option2: Yes I dive with both my compact miniature SPG and AI transmitter at all times…
Anything else doesn’t make sense to me …
PS: Use a small 3” SPG not the larger two-dial models with hard plastic boot that can feel klunky and cumbersome…