The WSM will also last a lot longer than the Kingsford.
My WSM is now 26 years old. Yet it never got the workout it did since I took the 5-step tutorial from GWiv several years ago. The tutorial alone is a solid reason to buy a WSM, because in 5 cooks you are on the path to intuitive smoke cooking. You will have fabulous results from the get-go, you won't waste hours and cost of materials following a learning curve.
I followed the Weber instructions to the letter, then later learned I was doing it wrong. Weber had me soaking wood, GAry said it increases cloudy smoke and creosote. Gary steered me toward clean burning wood fire charcoal. I also learned I want the nearly invisible blue smoke to caress my meat, not industrial strength smoke depositing bitter tasting creosote on my meat.
I also am confident in the process of cooking on my WSM, I don't babysit the WSM or nervously study thermometers. If I set up the fire correctly, then I have little to worry about. I can go back to the kitchen to prepare the sides instead of watching an inanimate object smoke.
The WSM is also versatile, it can be your everyday grill with the larger Weber kettle pulled out for company. If you had real estate for only one toy, then the WSM would be a wise use of that space.
Good luck!
Regards,