I've never seen electrically adjustable springs on any vehicle, but many US Gen II Monteros had electrically-adjustable shocks, which is what I'm assuming you're asking about. Mine were worn out when I bought my 95 SR with 130K miles. From what I've read here, they tend to have about the same life expectancy as regular shocks, which will vary depending on how hard they are used.

95 Montero SR
3.8 MIVEC, Advance headers, 2 1/2" exhaust, Magnaflow muffler, OME shocks & rear springs, 2" body lift, 3" tank lift, 4.90s, TRE front locker, factory rear locker, Roger Brown Rock Sliderz, 315/75r16 (35") tires, Sport big brakes