Buoyancy Control Devices (BCs) FAQ
Both are harness, backplate and wing type systems: The TransPac is a 'soft' plate using a semi rigid high-tech material. The TransPlate is fully rigid metal plate (your choice of aluminum or steel). With a properly adjusted harness, both are equally as stable. We are sometimes asked if the TransPac can have a plate "added"; the answer is no. While other brands do offer "hybrid" systems, because of the nature of the TransPac design combining hard and soft plates together wouldn't produce any benefit. The hybrid systems offered by other brands can best be thought of as a TransPlate with a lumbar backpad option.
We most often recommend the TransPac because it is always more comfortable and form fitting than the TransPlate. Even adding a lumbar backpad to the TransPlate will not make it as comfortable or form-fitting as the TransPac. If you want to add extra weight, choose the stainless steel TransPlate system. Most people diving double cylinders choose the TransPlate. Most people diving single cylinders choose the TransPac. Most people who dive drysuit exclusively choose TransPlate, most people who dive wetsuit exclusively choose TransPac.
The simple answer is "probably not". The STA is a product which predates modern backplate and wing designs that include pre-cut slots for cam straps. Using the straps threaded through the backplate snugs the tank and wing up very tight against the backplate and does not allow the tank to rock. Using an STA sets the tank farther away from the backplate and allows the tank to rock slightly by pivoting from side to side on the bolts. For more information read our article Single Tank Mounting with Backplaces.
Most wings offer the option of a "Remote Exhaust" (aka pull-to-dump) elbow or "Plain" elbow. The standard pull-to-dump convenience feature is present on nearly all recreational sport BCD jackets and the default configuration on many single tank back inflation wings; the plain elbow is the default on most double tank wings. Experienced divers avoid the pull-to-dump feature, because it's difficult precisely control the amount of gas released and they do not like pulling on the inflation assembly. For experienced and technical divers, as a result of their often horizontal position in the water, they use the OPV pull to release gas or hold their inflation assembly above their head and press the oral inflate button to release gas. Many divers view the Remote Exhaust feature as an unnecessary feature that is just something that could fail and therefore prefer to use their skills to trade off convenience for reliability by selecting a plain elbow.
The standard corrugated hose on the inflation assembly is usually about 16-inches long. Some physically very tall or large divers need a longer corrugated hose length of 22-inches. Longer corrugated hoses are also usually found on BC integrated alternate second stage regulators. Some technical divers, especially cave divers, prefer a shorter 12-inch corrugated hose to reduce the "danglies".