10 years, that is just getting broke in!! Most regs will go longer than that without a rebuild....not that I am recommending it. Properly cared for gear has a very long life. Wetsuits at least 10 or more years assuming you are not dving in a pool with them, that shortens the life a lot. BCs can easily go 15-20 or more years, again with proper care and limited pool use. With BCs and wetsuits they do tend to fade which in some minds means they are worn out. I don't consider simply fading to be ware, to be worn IMO, function has to be degraded. Ugly but 100% functional is not worn out to me. Regs on the other hand have basically an unlimited lifespan as long as they are taken care of, same goes for tanks. The life expectency of a reg is determined by how long you can get parts for them, the main components are not subject to "ware" as they are bacically support structure for the moving parts. They can be damaged by corrosion but that is caused by abuse, not use. As long as they are properly cleaned after a dive, the main parts will last multiple human lifetimes of diving. All the internal and external parts that are subject to ware or ageing are typically replaced during service. There are plenty of Scubapro and US Divers (Aqualung) still diving 40 plus years with no end in sight because parts are still available for them.