The Flat Top grills were produced for the Australian market to satisfy market needs. Most Australians still BBQ (Grill) on a flat top and only use the lid to cover the mess. They will fire up the flat top and get it as hot as they can and throw a piece of steak on. They then continue to push it around the solid grill plate finding all the hot spots, if any juice starts to ooze out of the meat they flip the meat over and continue to do this until the meat is like shoe leather. It takes about 6 beers to cook a steak, By the time they are ready to eat the steak they have well lubricated throats and the meat slides down unaided.
Well at least they do it something like that. The Australian traditional BBQ is done on a hot plate not a grill hence the Weber flat plate BBQs were made to get into the Gasser Market. (they are no longer sold in Australia). Australia now has a limited range:
The Spirit range (with an optional side burner) 210, 310 & 320
The Genesis (Black or SS) 310 & 320
The Summit (SS) 420, 450 & 650, and
The Summit Built in (SS) 440 & 640
My humble opinion is to do all grilling with the lid closed - Gasser or Charcoal. I consisantly get much, much better results doing this. When I demonstrate cooking on the Weber range of BBQs doing it this way and the customers try the results, the BBQs sell themselves, the store staff just facilitate the orderly procession of BBQs out the door. I continually have customers come back to see me 12 months or 2 years later saying how wonderful their BBQs taste now and the marvelous array of dishes they now cook compared to before just burning a sausage or a steak.
And now you know why all my friends love my barbecued food so much, it's moist, juicy, tender, flavoursome and cooked to perfection.
Regards