Because I host a lot of big parties - Block Party, Halloween, Home Brewing Party, etc. - my normal requirements for buying a grill are based upon size only. The wear and tear from moving the grill to party to party from the house, however, has taken a horrible toll on the old one, so I donated it to a neighbor with a much shorter and easier route to party central.
For the first time ever, I purchased a grill with more than just size and being cheap in mind. My requirements were the following: searing area (infrared), rotisserie, still had to be big, secondary rack, and it had to put out a ton of heat (BTUs).