The folks at www.uboatworx.com in Holland just redesigned their models to 2 and 3 pax. that will go up to 100 m. deep and will be classed by Germanischer Lloyd. The new models look awesome. I visited the factory last year and can see the redesign means a big improvement. There's a lot of crazy designs out there but it seems there's finally a personal sub available that's more than just a bunch of webpages with artist impressions or models that require you swim into them from below. Check it out.