I'm a member of clublexus forum, I joined up about the same time as AF before I bought my A4 when I was searching for car in its class. I've driven several IS250's, going back and forth with the A4. To me, the IS250's handling needs some major work. I thought the 1st IS250 I test drove was the bad one on the lot so I got in another one, but with same result. It drove like a shopping cart and the road noise was unbearable.. The IS250 I test drove had the premium pckg which is pretty much standard in Ca. I liked the keyless feature, nave with rear cam, and perforated seats. The only thing that turned me off was the car's handling, no way I would pay over 32k out the door for one. To me, the A4 was more worthy car.

There was also a thread in clublexus forum about what people regret for purchasing the ISxxx. Some stated that they missed their german car's handling and the "fun" drive.

The new IS isn't as reliable as you may think, some issues are seatbelt not retracting, someone actually had to test drive one without wearing a seatbelt(this issued was recalled earlier this year). Some are stalling when changing gears from P to R or from R to D(auto trans). Now, some are having clutch issues (manaul trans), grinding gears when shifting, loud clicking sound. That's probably gonna be a recall on the clutch plate

I'm sooooooooo glad I went with Audi, the only one thing I don't like is shifting lag in tip mode.

 

Go with the A3.
When I test drove the IS350 out of curiousity, I was deeply disappointed.
The 300HP car is as fun to drive as aCamry...no joke!
I almost fell asleep at the wheel.
The IS250 should be even worse.