I know of two people that have/had an FJ.
One of them was heavily modified for off-road (snorkel, lift, big tires) and was constantly having issues, for about the 3 years he owned it, it was likely at the Toyota dealer for 6 months during those 3 years. The lead Toyota mechanic said that the FJ's don't do well when modified.
The other is 100% stock and he still has it. I think it has about 130k on it and no issues at all.
99 Chevrolet Camaro Z28 M6 - 6.676 @ 103 in 1/8, 10.512 @ 130.2 on street tires, H/C/I
93 Eagle Talon TSI AWD 5spd - Built 6 Bolt, 16G Evo3, HKS 272 Cams - under construction
94 Mustang GT - 5.0 bored and stroked to 347, Vortech V1 @ 10 PSI, Tremec TKO 600 - PIA