What are some 2003 Toyota MR2 Spyder smt transmission problems?

The 2003 Toyota MR2 Spyder with a five-speed sequentially shifted manual transmission (SMT) has had its share of problems. The SMT transmission can abruptly stop shifting, causing the engine too over rev. Cutch and HPU pump failures are all too common, especially as they age. The gear shift actuator often fails or will leak because the clutch actuator rod corrodes and causes damage to the GSA seal. The SMT transmission was only used for a few years, at the time it was thought as revolutionary, a five-speed manual transmission that shifts itself. It seems that there was limited information available from Toyota on repairing the SMT leading many technicians to blindly make repairs, hoping for a positive outcome. Many owners often swap the transmission with a standard manual version to free themselves from the costly repairs.