Hi Rob,
I am not an expert on cars or Lexus. But I do need a reliable motor.
I bought one 2012 model last year and have been driving it since then.
Car has now 88k on the clock.
I do around 330 miles a week, swindon <-> Cambridge, in between I use it for commuting to work and other social stuff. All together around 330 miles a week.
motorway speed (from 50-70 mph on 3 motorways, M4, M25, M11 and then Cambridge and vice versa) I average around 60-64 MPG - in normal mode. Commuting to work in town I use the sport mode, just to be nippy around roundabouts. it still use EV mode in slow traffic. MY MPG drops to 58 MPG if I do long stretches (tested it once in sport mode).
by the time I get home at the end of the week, I still have a quarter of the tank. Filling it up these days around £35-£40. For the above trip each week, it uses around <=30 litres.
it need servicing every 8 months based on the above trip. it has been serviced by Lexus Swindon. no problems so far. You need to watch out for the brake discs. They wear out more than others. a pair cost me £500 including brake pads and other stuff (can't remember). it is not a frequent occurrence but it does happen more than other cars.
I bought it with Lexus extended warranty (includes excellent road side assistance and you can also add another driver for free), Lexus insurance, and I pay monthly for my services (3 yearly, one major and 2 minors services and MOTs). They all worked out cheaper for me than 3rd parties.
I have the one with Navigation, and it is hilarious :-) I have a funny accent, and the command Go Home becomes a search for Golf Club :-). it manages my phone pretty good and I can make and receive calls with excellent clarity.
in a build up areas such as Cambridge with large population of cyclists and in traffic you have to be extra careful and keep your distance as they cannot hear the car when it goes in EV mode, same goes for pedestrians and birds in the middle of the road.
hope this helps.