Inspections are a load of BS, and they cannot deny your warranty for not having them done at the dealer. If they do, take them to court.

I've never had an issue with warrantied repairs on prior cars that were Toyotas, or any other brand. My old Celica once had a throttle position sensor go out, and it was covered under warranty with no cost to me. Did I ever do anything besides oil changes? No. Did the dealer ask any questions about my prior maintenance history on any warranty repairs? No.

In fact, I turned down all of the dealer recommended maintenance. The trick with Toyota/Lexus is to not fool with them so much, and simply let them run. We've had Toyota/Lexus in my family since the late 1970's, and the prior advice comes from my dad, who states firmly that you shouldn't do unneccessary work on anything made by Toyota.

If you have doubts, pick up the phone and call Lexus customer service. You are entitled to work on your own car, and have inspections done by yourself if you so choose.