Suction side cleaners work pretty darn well for round pools, especially if they are not dished out or have a deep side. When you get different shaped or longer or have high coves, dished out sides, etc they will miss things because they just look for the path of least resistance and ALWAYS travel there so you have to persuade them to get odd spots. Most of them (mine included) have settings so the random patterns they take can be changed (larger circles, more sides, more side to side) I like mine ok except for whats mentioned above with odd spots and I would like something that doesn't require hoses as they sometimes get a bit tangled or twisted so you have to move it occassionaly.
Mine is a Lil Shark, the Tiger Shark is the bigger model. Aqua Bugs and Diver Daves are basically the same thing as the Lil Shark with the different top on it and they have wheels. Any of them work decently. Sometimes wheels can wear out, some have flappers that can wear - the more moving parts, the more that can go wrong on the suction sides but they are pretty basic. A leaf canister inline will also reduce the times you need to stop and clean out the skimmer. Some will not pick up larger debris, some will. Mine does and I also have the leaf canister.
