Barlow

Hey guys, My name is Chris and i'm currently the owner of a 1997 Mitsubishi Legnum VR-4, i am a BIG Mitsubishi enthusiast (with 7 owned cars since 2007, 6 have been Mitsu and 1 being an IS200), but i love all Japanese cars. I am currently looking for a new car that is more economical, not looking for a 50+ MPG car as i dont do a million miles a year, but with the Legnum being a 2.5 V6 Twin Turbo, it only returns 8 MPG (to be more specific, i put in £100 and was gifted 120miles lol) and thats regardless of how light or heavy my right foot varies . So, to get to the point, the car that i have my eyes set on is an RX400H, my old boss's wife had a 2006 model and it was really nice to drive and so smooth, with 2 kids it is also a nice family car! Also, with a 0-60 in mid 7's it isnt a slug either, although my Legnum does 5-6secs 0-60 (which i will miss), i am willing to compromise on power to regain some MPG's! I will be aiming to get around £5k together to get one and a few knocking about in that region of cost seem to vary between 120k to 170k miles. Now, i am quite educated on cars, especially Japanese cars, but i have no idea how reliable these vehicles are at this sort of mileage? Do batteries become extremely weak and not hold charge very long once these sort of mileages have been reached? If yes, what sort of price are replacement batteries? Same goes to the motors, what are these like? Generally, what common faults should i be looking out for? I am struggling to find any cars that come close to this level of quality and gadgetary for this sort of money? Other cars i have been looking at are IS220D's and Audi A6 3.0TDI's, but the IS220D is only 8.9 sec 0-60 and the 3.0TDI, you dont get a nice spec motor for this sort of money. I have a seen a few GS450H's for around 5k too, but not sure if this is slightly mature for my age (25 years old)? Any advice (good or bad) appreciated in advance. Cheers, Chris :D