If you have any hesitation, just book it. It's great value for your money, and if your trip is anything like ours, you'll see incredible things, spend time with wonderful people, and learn lots from some of the best guides your could ever ask for. Special shout out to Jack (Moyenda) and Masai (Paul) our guides from Cape Town to Livingstone, who made living in tents and riding a big truck with 22 people some of the best times we've had. Don't worry about it being a participation tour--that really just means you'll help pack up the chairs from around the campfire, might cut up some vegetables, and will take a few turns cleaning some of the cookware. If you're not uniquely lazy, you'll probably even enjoy the few assigned tasks which help bond the group--especially the dance of the dishes.
A few tips: pack light (you don't need that many sets of clothes), bring warm clothes for the chilly nights if you're there in winter (the right clothes and a good blanket make all the difference), buy yourself a good pillow when you arrive (you can donate it at the end), plan to do some of the optional activities (almost all of them were worth it), and keep in mind that you'll see some incredible places that you'll certainly feel the need to come back to for a longer stay. Also, the food is incredible, so don't worry about that. Plus, the toilets, showers, and wifi were generally clean, hot, and working adequately where that was advertised.