i have never heard any complaints of rust on the svx. the only major components that i have ever had problems with are rear wheel bearings, tranny, cv axles, alternator, teflon guide piece on automatic window, water pump, brakes, struts, camshaft seals (not replaced when my timing belt was changed), air conditioner refrigerant seal, idle air control valve, tranny mount, and really that is it.
i am sure every svx has its quirks. besides the tranny everything else has been some what reasonable. i paid a lot to get the window guide piece fixed and the camshaft seals because of the labor involved.
the 60,000 and 120,000 miles services are expensive because to the timing belt change. they way i look at is every sports car is expensive so it really comes down to if you love the car or not. i have put up with this cars problems because i can not imagine driving anything else. that is the bottomline.