Good advice ... equipment's only worthwhile if you have it on you when needed. But I'd caution about using an SMB as a lift bag ... unless you're letting go of whatever you're lifting and letting it fly to the surface without you…
Good point. I have never used a lift bag with an OPV, just the open bottom type — as in: hook it up, fill from second stage, and get the hell out of the way! That is how I suggest using an SMB as a lift bag as well.