Sams has one for 400 that is almost just like a commercial size. I bought one and it is great! Portable(for two people) and grills hot hot hot! Famous Daves BBQ uses the same one at the biggest food event in Denver, Taste of Colorado, and they are THE busiest booth there.
The one you are showing is nice, but there is no grunt grunt he-man feel to it that attracts the crowds. If you can possibly afford the bigger one, get it.