Don't want to tempt fate but my 2005 400h has just notched 160,000 miles and shows no signs of being anything else but a reliable daily driver. Just come back from Europe after a 2.5k mile trip - mostly cruising at 80mph and with the MPG indicator showing 32.8 - awesome!
OK, some issues, parking brake cables seized, auxiliary power sockets gone dead and CD player died. Found that the cable ends had fossilised - probably because of non use - and fitted a pair of cables along with some new brake shoes, now ace again. The power sockets and CD player are on my to do list.
My gut feeling is that this car will be capable of breezing past 250,00 miles without major problems and that is based on over 50 years of motoring in every thing from Austin sevens to modern Jags, and even Fords. Sorry no actual stats, just a feeling that tells you when you have a superbly made modern masterpiece of engineering.
Oh by the way, anybody got a spare £60k? cos I'd buy a new RX tomorrow!