If he's willing to pay full retail ($399), then you might as well have him purchase from Amazon through a TVWBB link (see below). That way a couple of good things happen:
1. This site gets a piece of the pie, helping it to stay up and going.
2. He can get free shipping directly to his home (no driving, gas and possibly sales tax savings, etc.).
No, that has not been my experience in the past. My experience is they use more fuel, but that's to be expected...they're a bigger oven.
And thank you for the Amazon plug. I know you have lots of choices as to where to buy, but buying a WSM or anything at Amazon using our homepage link generates a small commission that helps pay for web hosting, domain name registration, software licenses, and more.