Never used a little giant, but have heard a few things about them: 
Hatches one and two generally no problems, but after that - rates go down on sucessful hatching. The reasons seem to be because the bator is styrofoam and is very hard to clean extensively (as bacteria gets in between the packed plastic bubbles that makes up the material), bacteria LOVE incubators think of it as a warm wet bacteria heaven. Also, the lid edges and hinges tend to loosen or get worn down with use, so a secure fit is hard to maintain. This causes bigger fluctuations in heat and humidity. 
For the same amount of money (and if you are researching first, buying later it is worth looking into) make your own. Use a plastic box, not stryrofoam. You can get turning trays - buy this assembly first so you get a casing (plastic tote) to fit. Plus, you can make it as big or as small as you like for little cost difference.