Best place for Dim Sum in Vancouver?
A question fraught with difficulties!
If you want to stay within Vancouver proper, my two favourites at the moment are Dynasty (Broadway and Willow) and Kirin (12th and Cambie). Both are quite upscale with better-than-average service. Dynasty is about 20% more expensive (with a table for six we recently paid $20 each vs $15 at Kirin).
Heading out to Richmond opens up a lot of options which is both a blessing and a curse. There actually isn't a place I can recommend wholeheartedly out there at the moment as it seems every place is inconsistent in my experience. You could have a look at comments on The Jade, Fisherman's Terrace, Sea Harbour, Red Star, Sun Sui Wah and other heavy hitters to see what you think.