Economy - I've got up to 50mpg in mine, which I'm very happy with. Yep, it's less than the 60mpg quoted but I don't think you'll ever see close to the quoted figure in any car. It's too much a controlled conditions test. It's a test that gets consistent numbers between different manufacturers cars but it also sees silly results like the 100mpg+ figures that are quoted for plug in hybrids.
What I'm really happy about is that I'm losing much less against the quote than with the CT I had before. My sig has the Fuelly link to my IS and this link will take you to the numbers I was getting on the CT : http://www.fuelly.com/car/lexus/ct200h/2011/Sleepypete/91945
CT - quoted 69mpg, achieved 48 average, although I was seeing minor improvements in that to a consistent low 50s after I stopped bothering updating Fuelly.
IS - quoted 60mpg, achieving 46 average and improving with every fill up. My current tank is reading 53.5 on the computer which will turn into perhaps 49 at the pump.
So that extra performance in the IS gives extra flexibility which helps out the mpg.
Performance ? It's a 220bhp car with double the torque that you'd expect. I rarely drive in Sport now (don't have to !) and I drive in Eco in town to tame some of the drive-by-wire responses (the brake can be a little choppy in mine at low speed). Off the line, you have to be careful following people because of our CVT gearbox, our car continues to gather speed while they're changing gear.
That CVT gearbox is worth a mention actually. The CT felt quicker than the 10sec to 60 car it was. It felt as quick as my Puma (9sec) and almost as quick as my Focus ST170 (7.5). The reason is that the CVT gearbox lets the car give you everything it's got, every time you ask it to. There does seem to be a little bit of motor lag in Normal that goes away in Sport.
The IS has enough power to make pretty much anything go Bye-Bye behind you at the lights, plus it has a chassis which just eats sharp corners for breakfast.
Happy IS300h owner here - it does that magic combination of handling, power and economy :hocus-pokus: