Automotive standard has always been 50k but alot of cars can go more I sug no more than 75k they mY not leak but the seals inside can go bad biggest thing they can destroy your tires chop heaven if they are really bad
As for what kind Monroe are good for street use if you go offroad alot get some KYB or an aftermarket shock designed for abuse
"CMR TUNER" [email protected] 1/4 with a 7.32 1/8 custom long/short bars by "Me" Turbocharged 392 on 9psi S475/96/1.32 . Running thru an A518! [email protected]
Shocks on my 03 were dead at 50k. Had a driverside rear that had failed without leaks. Replaced them with Monroe's standard length in the front and 2" shorter in the rear. I used the online Monroe specification chart to select the shocks.