Good choice with the Weber 22.5". Some differences between the Orginal Kettle (it used to be called Silver) and the Original Premium Kettle(it used to be called Gold) is the charcoal grate in the silver is concave and the gold is flat. It's harder to hold the charcoal to one side on the silver for smokes but it can be done with the help of foil. The silver has the one touch ash clean out as well but it doesn't have the ash catching bowl at the bottom like the gold model. The gold models come with the charcoal baskets for two zone cooking like Timberjet showed. I grew up with the silver "plain Orginal" models. Here in Illinois these models are $99.00 verses $149.00 for the Gold. I have to say that all the Original models have a slight wobble because of only three legs. This gets worse as they get older. The Performer series are much more steady plus like Timberjet pointed out you get the extras of the Premium (Gold) models and a conveinent table attached.
For the price of the Performer you could get the 26" though.
Great customer service; The 26" Gold I purchased last year had bad welds on the bowl where the legs are attached and they failed last week on 03/22/15. The lid was dented as well. On 3/23 I called Weber and on 3/24 I received a new lid and bowl, free of charge.
The following picture is after I put the new lid and bowl together. Back in action for a re-seasoning with smoked sausage and double smoked bacon on 3/26.
Register your grill with Weber customer service as soon as you receive it. Any issues with parts and they will send you out new parts, no questions asked.