i always like to encourage people to try new ways of doing things. i think i remember a thread about trying this. perhaps it was yours. and if this works for you i think thats great. but can you pls breifly explain what your rational for doing this is ? i am genuinely interested.
for me, i have been in conditions where a single bm plus a 19cf pony (or larger) worked great. i wish the shops we use in coz had this as an option. i think coz would be a good place to do this.
i enjoy sm with a single tank, but if i was going to sm two tanks, i think i would keep things simple by using the same size tanks. i am trying to find the advantage to having two dismilar tanks.
Side-mounting 2 different sizes (ex: 80cu & 40cu).
Speaking of which, I should post an update to that thread.
The advantage of doing a 19cu pony (versus only 1 tank) is almost entirely for redundancy & emergencies. I do a lot of solo-diving. The other advantage is mostly weight managing tanks above the water, which is mostly an issue for me when diving off my friends boat and getting setup to dive quickly.
As a quick note, today I bungeed the pony, whereas I didn't last time. I definitely prefer bungeed, even for a pony.
How bad is the roll with SM one tank, say a 100cf steel...and an Xdeep Stealth.....I imagine I will be rolling a decent amount, not super relaxed.
Not that bad with an AL80. If I'm moving, even a relaxed swim, I don't notice it. Hovering, It's a slow lean to the left about 45-degrees, but it's not that extreme. I've had worse roll on a backplate setup with weights on the cambands.
Steels? I don't know.
Personally, I see no problem with putting a weight on the pony, but I haven't done it yet. I'm not an expert, but I think the issue with weights on tanks is mostly around your own buoyancy when your tank is not equipped, if for example you had to doff the tank for a restriction, to fix hose routing, or some emergency. If it's just for trim, I think it's fine.