I have a Backwoods Party. It has over 1500 sq inches of rack space but if cooking multiple butts, more like 1000 sq inches. It's about 4' tall and just under 2' square. I think this is a great size for the backyard, I can easily smoke 2 butts, 2 packers and 4 baby backs at one time.
It is possible to do a full competition with only a Party. But from what I've seen, often a team with a Party will also have another smoker or grill - depending on how much they cook.
People have mentioned the weight of other units. The weight of the Party is one of the pro's for me (140 lbs). I'm able to tilt and slide it into my truck bed without a problem or harm. I don't think that could be said about insulated verticles this size from most of the other makers. I'm trying to sell this smoker and this is something that I'm going to miss alot as I get my Party and all of my supplies in the back of my Dakota to go to a competition.
I also like that the Party can be used as a grill, which is very nice for competition chicken. Converting to a grill is as easy as taking the water pan out, that takes about 5 seconds.
The only reason I am selling the Party is to get a larger Backwoods to help with some catering I have lined up. I'm even half way considering purchasing the Competition regardless if I sell the Party or not right away. It's a good smoker and I'm sure I'll find it a proper home prior to spring.
I don't think you can go wrong with Stumps or Spicewine either, but wanted to share some things that I feel are benefitial for me and the Backwoods. The Competitor weighs about 350, I hope I'm able to tilt and slide that into my pick up. I put a moving blanket under it and it slides easily so I think I'll be able to - but it will pretty much fill my truck bed. So I'll have to figure something out to get my stuff to my brother's house when the competitions are closer to his house.