Just picked up my 2010 IS250C in Ultrasonic blue/Black on Friday. I traded on my silver 2007 GS 350 AWD.
Here are my first impressions:
The cockpit is roomier than my GS. The specs verified this. I was very surprised.
I downsized the engine from a 3.5 on my GS to a 2.5 on my IS. I'm quite happy with the lower power.
The car rides and handles better than my GS due to the LACK of runflats on the IS. I never liked the runflats on my GS since they rode hard and made handling a bit twitchy.
The electronics are better than the GS including better Bluetooth integration and the new iPod and Aux integration. The mav system is now HD-based so appears ro respond faster.
The car is Lexus quiet with the top up.
I agonized over the color but I now like the ultrasonic blue very much.
The iPod integration does not show playlists but does read Songs, Podcasts, and Audibooks.
The nav screen appears purple in bright sunlight...but you can still read it.
The front parktronic only covers the corners since there are no sensors towards the front center.
I don't care for the external radio antenna on the right read.