I have heared of people trying to use reptile rocks and nothing good comes from it. For starters, they are expensive as hell, especially if you are going to use them only once. They do not have any way that you can adjust the temperature.Same goes for heating pads. Button quail have very specific needs - the smaller the baby bird, the more leeway there is for something to go wrong because they just don't have the body mass to compensate for it.Under-floor brooders are generally considered a bad idea - they have the potential to burn the feet of the chicks.
A heatlamp is cheap, more convenient, more accurate, provides a better quality of heat and is by far the best option. You don't need a huge fancy bulb from the feed store that costs 20 bucks - for 5 buttons just get a red-tinted 40 watt bulb from
walmart for a buck or two or better yet for a couple more bucks a red-colored 100watt flood light from home depot and put it in the fixture of an old lamp from the thrift store. Make a tin foil cone heat deflector for it, hang it in the box so that the center of the heat beam is 95 F (this may be only a few inches high for low wattage bulbs) and bob's your uncle. They only need heat for 2-3 weeks. More nice things about heat lamps include the fact that because they are red, you can sleep with them on and the light doesn't bother you (I once had 6 brooders and 6 different lights on in my room!) and because they emit light, you know right away when they aren't working. You can get reptile heating elements that fit into a light socket from the pet store, and I thought about using that once but if it blew a breaker, I wouldn't know right away. Baby chicks don't survive long without heat so if something isn't working right, I want to find out immediately. And those things aren't cheap either.
I definetly would not keep them in the bator for more than 24 hours, would prefer to get them out by 12 and if they are fluffy and fully ambulatory at six hours, I take them out. I want to get them eating and drinking ASAP.
I would do some reading about how to effectively brood baby chicks. There are a lot of seemingly easy short-cuts and improvisations out there but nothing works quite as well as the good old heat lamp and cardboard box. Brooding buttons is no different than brooding other quail (or chickens and turkeys for that matter) except for the fact that everything is on a smaller scale and you have far less wiggle room for mistakes!