I had a 15 year old Summit S670 and the cart has rusted out on it.  Finally decided to buy a new Weber but didn't need all the bells and whistles and the price of a new Summit.  The new Genesis cooks really well and still gets super hot even without the searing burner on but it's definitely lower quality steel and construction then my old Summit. For example,the Summit lower cabinet was fully sealed but this has about 8 inches under the grill top open and the drip pan is exposed.  Animals could easily climb inside. I question if the new grill will last 15 years like the old one.