I have a Torsen type in an R200 for my 300zx. After several years (yes years) I thought it would be wise to open it up & see what it needed for service. Waste of time, there was nothing that appeared worn. It came with the car so I have no info on price or installation. It works like a dream, no inside wheel spin but you can push the car by hand in the paddock and still turn, unlike a welded diff. Glad to read the suff on the VLSD's though as car #2 needs something.