Hi Geoff. Had my RX for just 6 months now and delighted with it.
Previously had an IS250 and IS250C, so other than the hybrid bit, similar cars to yours. I changed to the RX because my back was suffering climbing in and out of the 250C.
Mine is a 2013 (March) Luxury and is the facelift model, easily spotted with the DRLs. It has everything my IS250 SE-Ls had except for illuminated scuff plates and ML stereo, so very well equipped. The standard stereo is more than adequate in a motor vehicle, I didn't notice a difference from the ML (and I'm a bit of a HiFi geek).
My vehicle is a 2 owner with full Lexus SH and the 60,000 was done at 53,000 including the spark plugs. I paid just under £20k for mine at 55k miles, so you have plenty of scope with your £24k budget.
My advice is to take your time, the right one will come along. I searched for a few months before settling on mine.
Good luck with your search. Let us know what you buy please.