general problems of the 2001 Lexus GS300

I am deeply disappointment with the steeing on my 2001 Lexus Gs300 and I've only had it for a year. It is so loose it is almost scary. I can turn it almost a half turn at say 5 mph with almost no change in direction of the car, that and the fact that I can do this with one finger on the wheel. I've had an incident, where I lost control of the steering (shaking steering wheel) and cause me to hit the curb on a local street. I have been reading the posts on clublexus about the l-tuned steering ecu and figured that had to be a solution (even though half the posts only say it affects high speed feel). However, I ran into a friend today with a 2000 gs400. I test drove his car and the difference was amazing (and we both have the exact same 17" tires). His steering was firm and direct and is completely stock without the l-tuned ecu. Now my question - how in the world am I going to convince my dealer that I have an issue with my car's steering? I know there is an adjustment that can be made, but from other posts it seems as if dealers are reluctant to do this.