I always thought X-38 was gold plated overkill for a rescue vehicle. If they want a rescue vehicle then they should bring back the Apollo command module (CM). The CM was configured to hold up to 5 people for the Skylab program. They could attach two CMs on the ISS and thereby provide escape for up to 10 people. The standard counter argument is a lifting body has cross range capability along with precision landing. However that argument is utterly bogus IMHO. For a CM rescue capsule, they simply need an inertial navigation system coupled into the GPS along with a reliable radio transmitter. When the capsule fired its retrorocket, it would downlink its entry vector. The people on the ground could quickly work out where the capsule would land and send a rescue team. This would be much more cheaper (and robust) than a lifting body rescue vehicle.

Gary