In a broad sense, paintball hoppers are classified as either gravity or electronic.
There is a common misconception that gravity hoppers, because they are less expensive than electronic hoppers, are bad hoppers, and this isn’t actually the case. They just serve their own purpose. For players who use pump or tactical markers, a gravity hopper will do the trick because shooting very fast isn't a priority for these players. Also since pump players don’t use as many paintballs as a speedball players do, it would make more sense to have a gravity hopper like the ones from gen x global. These kinds of hoppers hold 50 or so paintballs, and this is a better option as opposed to something that holds more because loaders that hold more paintballs are designed for a different type of game.
For players who focus on trying to prevent chopping, shoot faster, and have a more consistent feed, an electronic hopper would be the choice to make. There is quite a variety when it comes to electronic hoppers. There are relatively simple ones like the Empire Halo Too and the JT eVolution.
Technology wise, the Halo Too is a real step up from other hoppers, with a device inside that rotates paintballs through, forces them down the ball stack and through the feed neck. Then, there’s the Empire Z2, essentially an upgraded Halo Too with features that create more convenience for cleaning and maintenance.
Going to the higher end electronic hoppers, there is a great deal more technology involved. The Virtue Spire 200 and Spire 260 are extremely easy to take care of and maintain. The technical build of these devices allow for them to hold significantly more paintballs than the basic hoppers, and they operate in way to maximize the amount of paintballs shot at the fastest speed possible.
The same can be said for hoppers like the Dye Rotor and R2, as well as the HK Army TFX. In the realm of higher end hoppers, deciding which one to get comes down more to personal preference of the player, which includes factors of both functionality and aesthetic design.
Choosing a hopper really comes down to what you need to get out of it.
For even more info about the differences between hoppers, check out the video below!