I've purchased 2 new nissans in the past 6 months (Altima SL in Nov and Murano SE in March) from Rosenthal at Tysons Corner. I'm a long time N.VA resident so have bad memories of slimy sales men at Rosenthal when i tried to buy my first new car (slicked back hair, recycled business cards..) back in the 80's.. in fact i bought 3 VW's during the 80's/90's at Stohlmans down the road because i thought Rosenthal was too slimy.
Anyway when i was buying the Altima I tried Browns Nissan in Sterling but couldn't get them to bring their price down...seemed nice enough but couldn't match my price..
Used the Nissan corporate web site to find who had the car i wanted in stock - and headed to Rosenthal. I dealt with Freddy Barrera - had the car i wanted in stock (SL, leather and no sun roof - too tall), very direct and business like without the games, and I got the price i wanted.
Went back for the Murano last month and same treatment.
So now i'm saving for the 350z this november...
good luck