When Scuba diving what is better back inflate BCD or jacket style BCD?

Answer 1

There are several types of BCD, all have their advantages and disadvantages.

Old style horse-collar BCDs are uncomfortable to wear, and cumbersome to take on and off, but are the only style which will keep the head of an unconscious diver out of the water at the surface.

Jacket style BCDs are popular and comfortable, but can be bulky, both in the water, and to pack in a suitcase when travelling.

Back inflate BCDs are becoming increasingly popular as they are smaller and lighter. The downside is that they give less bouyancy, and lack the pockets and pouches of larger jacket style BCDs.

Increasingly popular are backplate-and-wing style BCDs (usually abbreviated to "BP/W"), used by cave divers and technical divers. These have the advantage that they are modular, so one can chop and change the parts (to dive double tanks or single, or with a larger or smaller "wing"). They are very small, very streamlined, and very tough. Because the bouyancy bladder hugs the tank, they keep the diver in better trim. But they contain no pockets for carrying small items like torches, and they tend to be more expensive that traditional BCDs.