I'm curious about Pasara. Haven't tried them, but tend to stay away from chains. It might mean they're good, but usually means they're "good" to a more toned-down, Americanized taste.

SO MANY Thai restaurants in Alexandria though, one or two have to be great!

Nothing good in Alexandria (although we haven't tried the one at Carlyle). I go to sam phao when desperate, but the best Thai in the area is elephant jumps in falls church. I also like Thai noy in arlington. Both are worth the trip.