Sir,
Gelato and ice cream may be made in the same machines. You can also use them for sorbets and sherbets. The only differences are the names.
The first decision you're going to have to make is whether you want a maker with it's own compressor or not.
Most compressor machines are strong enough so that the base (aka the pre-frozen mix) does not require pre-chilling. Even with cold base, they are significantly faster, and that's a good thing. It means the ice crystals in the will be smaller; and in turn, that means the frozen cream will be smoother. This makes them better -- but only slightly better. On the other hand, they are quite large, heavy, and therefore no picnic to move around and store. They are also very expensive.
The other machines, which generally use a pre-frozen (in your freezer) bowl to remove the heat and freeze the cream. These machines require hours more than the other type. Enough time and foresight to both (a) freeze the bowl for a few hours before using, and (b) chill the base well, before putting it in the machine. If you use them a lot they also require enough freezer space to store the bowl in the freezer. On the other hand, they are small, light, easy to store (outside the freezer) and cost under a hundred bucks. The consensus choice around CT seems to be Cuisinart. We own one and concur.
Some types of cooking equipment that have to clear a quality threshold before they really function well or where the cheaper ones are so much more difficult to use. I'm not sure you can say ice cream makers are or are not among them. You do want to avoid the absolute cheapest, but the better residential machines are wonderful.
Bottom Line:
The performance advantages of a machine with a compressor aren't great enough to make it worth its size and weight for most home kitchens, and when you factor in the extra price... the little home machines seem like the obvious choice. Unless you're doing a lot of ice cream -- averaging more than a gallon a week, or need to keep four or five different flavors on hand -- one of them should do fine for you.
Cuisinart.
Hope this helps,
BDL