Though crested geckos can do fine with baby food, it's not the best diet for them, Babyfood by itself isn't a complete diet for them. Other things should be added to the babyfood, such as bee pollen and something else that eludes me right now. Also most baby foods are very high in sugar, which isn't good for the geckos at all. All natural, no additives type babyfood is better. However it is much harder to ensure they are getting the proper nutrients with babyfood,as you either have to mix meat based babyfood in with the fruit based, or offer insects for protein, especially with young and growing crested geckos.
It is much better to just buy the Crested Gecko Diet, which has been specially formulated to meet the dietry needs of crested geckos. Thus you dont have to give them anything else. However, alternating between the CGD and some live insects, especially for baby crested geckos and growing juveniles, is much better for them.
Crested geckos I find are very easy to keep, though they do need a taller cage than a Leopard gecko. They also need different heating/lighting needs. Crested geckos can be housed at room temperatures, if your home typically stays between 68-80F with 75F being the best you don't need any additional heating or lighting. THey also do great with papertowel substrates as long as they have alot of climbing branches and cover (these can just be fake leaves/plants or live plants). They can also be kept in a 15-20 gal tall tank or equivilant. Leopards kept singlely can be kept in a 10 gal tank but the size difference for single members of either species isn't very much.
Leopard geckos do need a hotter environment with basking spots in the high 80's to low 90's, with undertank heating being best. Both are nocturnal so UVB light isn't an issue. Crested geckos are a bit more handable than leopards but neither are hold for a long time type lizards. I don't think the price of either is much different for normal members of each species. However, crested geckos tend to have a wider range of pattern and color naturally than normal leopard geckos. High end morphs of either species are pretty much the same price, low end crested geckos may still be 2-3 times more than a normal leopard, from a show or breeder, but in petstores, they are almost the same.
At the Toronto Reptile Expo, I didn't see any normal leopard geckos for sale, but was able to get crested gecko juveniles for under $80. I personally feel the crested geckos have much more appeal to them than a leopard gecko, but I have never owned a leopard gecko myself (mostly because I just don't like leopard geckos much on a strickly appearance sake). I find crested geckos look more exotic and 'cute' than leopards, no matter what morph they are.
Besides, crested geckos are funny when they scrurry up your arm and perch ontop of your shoulder or head. LOL