Well,... I just got back from a trip to South Dakota & whilst gone I finally got my LP 85's doubled up, at the encouragement of my instructor. I also got another regulator & some gauges & what not, so should now be all set. Man are those things heavy! I'm planning on going to Pennyroyal Sat. to "test drive (or in this case dive)" them with some people who are familiar with diving doubles (thank goodness- I won't have to try to do it alone). Hopefully I can get familiar with them quickly, so I can finish my Adv. Nitrox course soon. I'll let you all know how it goes after the dives Sat.