Midwest stocks four bottle fillers: The Fermtech Plastic filler, a plastic spring tip filler, the 1/2" bottle filler, and The Ferrari Automatic Bottle Filler.
The Fermtech Plastic filler is the one included in our Homebrewing Equipment Kits, and is also the least expensive. This bottle filler will work just fine for most homebrewers for a long time. The only difference between this one and the spring tip is the valve; the Fermtech model has a ball valve that works on gravity (when you push down on it, the valve opens, when you let up the valve closes). This valve works great 95% of the time, but occasionally the valve does stick a little bit. Most times this can be avoided by making sure that you clean the filler thoroughly after each use.
The Spring Tip filler has a spring valve that works much the same way, but since it has a spring, the valve will not stick open. The spring valve is on the top of the filler, which means that it empties itself out when the valve is released.
The 1/2" filler requires a length of 7/16" tubing as well as a 1/2" spigot to run from your bottling bucket to the filler, and fills bottles much faster.
The Ferrari Automatic Bottle Filler shuts off automatically when the bottle is full, and the fill-level of the bottle can be adjusted.