Hi
I have a 1998 2lt Diesel Turbo (Rover Engine) mine has done 140thousand miles apart from a few issues just recently It still feels as quick and astrong as when I first Got it 5 Years ago avaging between 35 and 40 miles a gal Best i've had was 44.6 that was down to Dorset. I off road it check out the Link at bottom, Only broke down once Due to starter motor going.
there are now a few thing going but thery are all wear and tear The latest is i think the Diff bushes need changing as there are nock from the rear when on left and right lock. One thing i will say if you go for a Diesel weather Rover Diesel or TD4 check the pipes to the Turbo and EGR vavle, The carbon had built up so much in the pipes the diamater of pipe was the same as a Biro Pen.. apart from that has been a very reliable car. Like anything else keep it serviced regular and will last.
The only mods i've done is put Falken Land/air Mud snow Tyres on it, Put Mesh between the Grill and rads to stop any stones hitting the rads,and the tray under the engine we now only unbolt the black placstic tray rather than taking the whole frame of when changing oil filter.. there will be some more mods soon just working on them
hope this helps
Rob