I agree with the assessment of Silver Spring and Rockville as well. I bought both the '01 RX and IS from my salesperson, Kambiz, in Silver Spring. Rockville was pretty bad, didn't want to talk much about the car itself, but went straight to dismissing Edmunds' prices and drawing its unreasonable bottomline quickly. In terms of customer convenience, Silver Spring picks up your car for service and drop it off at your residence or office at the end of the day. In addition, if you decide to drop off the car yourself, their entire fleet of loaners are Lexus. I heard it is the biggest fleet in the aera. My wife recently used that service and thought it was wonderful. The service person drove a brand new RX by himself to my wife's office to pick up our RX for the scheduled oil change. He even left the key to the brand new vehicle with my wife, in case she needs transporation to go somewhere.
Price wise, Kambiz of Silver Spring, was knowledgeable about the car, the market, and the various sources of prices consumers use. He was willing to negotiate for a fair price. On the same token, I'm not stingy to tag on a fair amount of profit to the invoice of the vehicle. I got the RX fully-loaded for $38xxx and the IS fully-loaded for $31xxx without losing the respect I deserve. Both buying experiences were positive.