I have three Wizards, four Generals and five MacArthur Cobs.
The Wizards are hands down the most consistent and highest quality. The walls are thick and dense, so much so that I carved two of them out to a much larger bowl diameter. At two inches deep it's not quite as cavernous as the three inch chamber of the MacArthur Classic, but it's much deeper than I could ever want.
Quality on the General Cob has gone up recently as well, they now come with plugs where last year they didn't, and I find the finish in general a little more thorough.
For flakes the MacArthur Classic will guarantee that you can fit virtually any flake (it's 3" deep), and it has the skinniest bowl so you won't need to stuff half an ounce in there to actually get a good fit. The General has a 2.25" deep bowl, but it also has the widest chamber that ships on a Cob, so it's the cob that I recommend most for... general smoking.
The Wizard is somewhere between the two, but I find the Cob itself to be of the highest quality.
One thing that must be noted about the Wizard, it has a standard Vulcanite Churchwarden stem. Which sounds like a positive thing to a lot of people, but it drastically changes the characteristics of the pipe. The standard stems have a very open draw, and the long Vulcanite stem is actually one of the most restrictive I've ever encountered. I've smoked a lot of bowls with stems like that though, so it's not like it's the end of the world.
My recommendation is to get both a MacArthur Classic and a Wizard, that way you'll get to play with two chamber diameters and two draw types.
