How often do you change spark plugs?

[Kira]

2006 tacoma V6 with 125K miles and plugs have never been changed.
2007 FJ Cruiser with 150K mile and never been changed.

Is that good? Plugs sure do appear to 'wear forever' now-a-days, but....

Put another way: One owners manual says 'platinum plugs @ 100K'. I loved knowing definitively.
Plugs a little early I can live with. Now it seems they might be 200K items! But sometimes they burn, no?

 

[Bullet]

Is that good? Plugs sure do appear to 'wear forever' now-a-days, but....

Put another way: One owners manual says 'platinum plugs @ 100K'. I loved knowing definitively.
Plugs a little early I can live with. Now it seems they might be 200K items! But sometimes they burn, no?

IDK. The vehicles seem to run fine. Out side of the warranty the only work i remember both having are the front brakes, PS fluid, transmission fluid(at approx 125L miles on both) , coolant, diff fluid, head lights, Evaporator on the FJ, and 2 bad ujoints (one original and the second the replacement) on the Tacoma, replaced.