I owned a G60 for 18 months and loved it, until the crank bolt let go 🙁 The power from the supercharger was great, and had torque from low down the rev range.
Owning it wasn’t too expensive when compared to modern cars, but be prepared to buy some spares second hand as some parts are discontinued or prohibitively expensive.
In terms of VR6 vs G60 its swings and roundabouts I think. The VR6 engines will need the timing chains/tensioners replaced as they get older, a job which is around £1k I believe. On the flip side, the G60 supercharger needs rebuilding anywhere from every 20k to 60k, depending on which size belt pulley is fitted (smaller pulley = more boost)
Bodywork and corrosion doesn’t tend to be too much of an issue but mine came with many little niggles. Look out for broken sunroofs, faulty spoiler activation, and if you get a G60 for gods sake get the crank bolt changed! Also make sure you get paperwork to prove the supercharger servicing, if it goes bang you’ll have to buy another at £400+ and they are getting more and more rare these days.