I can understand your concerns, and I had the same concern before I got my grill, but I've cooked for good size groups on this thing...
Check out examples my blog... (click on my username and there will be a link in my profile)
I hate to send you to other boards but (smokin' remove this if needed) this post demonstrates some volume on the PG1000 -
Cooking for a Large Group on the PG1000 This is a great grill and you can put out a ton of food.
Good luck in your search, and as Smokin' said most of the info/users on this board are going to be able to give good info on Cookshack products, but there is lots of info on other cookers at pelletheads.
Regardless, pellet grills in general put out some great food and you'll be glad you went with a pellet cooker.
Nordy