Nope, but not sure I want to tow around a 30 lb wing either. Looks to me as if this is becoming at least a three wing hobby, warm water, dry suit and doubles. I was stuck on the 30lb, 40 lb question also. With a dry suit I was needing 30 lb's of lead, so maybe I would make it, maybe not. Then I had a night mare, I am at the back of a boat, take off my rig, with my pony, and it sinks. I have to get a student to go down and get it for me.
A 30 lbs buoyant drysuit is at the top of the range, but not unknown.
Lets assume you have a 32 lbs buoyant drysuit, and are using a steel tank and Stainless backplate. The plate and harness are worth about 6 lbs and the empty steel tank about -2, and a reg is about -2 that means your rig will provide about 10 lbs of ballast with an empty cylinder and be about -18 with a full tank. Even the worst conceivable pony set up is not going to be 12 lbs negative. How again does your rig sink with a 30 lbs wing?
So maybe a 20-25 wing for warm and a 40 for cold.
The largest singles wing we make is a 40, and you will have a hard time convincing me you need one. (Most of these are sold to PSD divers who are vastly overweighted doing zero vis searches on the bottom)
Any bc needs to be able to float the diver's rig at the surface if they ditch it with a full tank, and be able to compensate for the maximum change in buoyancy of the divers exposure suit.
How many single tank rigs will be more than 30 lbs negative? I haven't seen one
How many wetsuits will be 30+ lbs positive? I haven't seen one of these either.
How many drysuits will be 30 lbs positive? These I have seen, but it has always been with undergarments necessary to long exposures. Long exposures require more gas than most can get from a single tank.
True warm water diving can be accomplished with very small wings.
Consider a SS plate, reg and full al 80. Together these will be about -10 lbs.
Consider the typical 3 mm full suit. 4-8 lbs positive is typical.
If your rig is -10 and you suit cannot loose more than 8 lbs of buoyancy due to compression you can use a truly tiny wing.
Tobin