There are several RV toilet brands that are known for their reliability, including Thetford, Dometic, and Aqua-Magic. Within each brand, there are different models that may offer different features and levels of reliability. One popular and highly rated Thetford RV toilet model is the Aqua-Magic V, which is known for its durability and ease of use. This toilet features a sturdy plastic construction, a full-size seat, and a powerful flush system that minimizes the need for additional cleaning. It also comes with an antimicrobial seat that inhibits the growth of odor-causing bacteria and mold. Another popular RV toilet model is the Dometic 320, which features a ceramic bowl and a high-pressure flush system that helps to minimize odors and keep the bowl clean. This toilet also comes with a full-size seat and a convenient foot pedal for flushing. Ultimately, the most reliable RV toilet for you will depend on your individual needs and preferences, as well as the specific features and design of your RV. It is recommended that you do research and read reviews to determine the best RV toilet for your particular situation.