The people giving you advise must be the conservative "gaddi manual hi honi chayee di" lobby.
Khair, there shouldn't be any problem with a car that's 10 years old in terms of the gearbox. As advised by dmx999, just drive it and see if the gears shift smoothly- if there's any jerk between the shifts, then it has an existing problem, be it small or large. Usually automatics built by Japanese manufacturers are bulletproof and don't go wrong unless someone really screws around with them.
Do keep us updated on the car if you plan on pursuing it.