It is extremely stable under water and has the best set of instructions going. We tested the Trans Pac with weights, and it scored lower than it did during 1995 tests with pockets and no integrated weights. However, the Trans Pac's weight system still loads and ditches better than several other BCs evaluated here. These two very different BCs share the same strengths and weaknesses. In a world of poor BC pockets, the pockets on these BCs are excellent.
Air trapping is as close to zero as possible, and the shoulder dumps are extremely efficient.
During ergonomic testing, valve performance was excellent on both BCs. During mechanical valve flow tests, the Equipoise was outstanding, but the Sirene was inconsistent, resulting in a lower score. Both BCs are oversized, so you may need one size smaller than you think. When the weight system is used to capacity, including trim weights, there is a tendency for the diver to turn turtle under water. Also, at max capacity, the weights tend to fall out unexpectedly.