Suggest you research this elsewhere, it's clear most of the people here don't know wtf they're talking about regarding Moda.
I love Modafinil as well, and have used just about every stim out there. Very long lasting, clean, no jitters, no tolerance, no addiction, no crash. It's not even a stimulant, but a "wakefulness agent". Stimulants "borrow" energy from the future, even caffeine, Modafinil doesn't.
After an initial period of a couple weeks, any minor sides typically disappear. You must take it no later than 10AM to avoid sleep interference. It's not that you can't sleep on Moda, but it will prevent you from entering REM, so you won't be as well rested the next day. That's why you hear some of the clowns here talking about insomnia and becoming emotionless. It's a side effect of REM depravation because they're not using it correctly.
There's a huge variation between brands, Modalert is the best. The reason is pretty interesting. While synthesizing the chemical is fairly straightforward, Teva's Provigil, the original, uses a proprietary crystallization process that makes the drug 80% more bioavailable than "formless" amorphous type most of the generic manufacturers make. Sun Pharma, manufacturers of Modalert, is the only generic maker that licensed this process from Teva. So the experience with Modalert is significantly different than other brands. The others often have unpredictable effects that at best make it seem like it's doing nothing, to at worst headaches and generally feeling like shit.
Quality Moda is like designer caffeine. One pill that gives you a jitterless boost for 12 hours with no crash, day after day without having to increase the dose. In quantities of a few hundred it's 75¢ a tab, a fraction of a cup of coffee.
On top of all this, long term Moda users consume 30% fewer calories on average than non users. I often stack this with Clen and GW50516, almost effortlessly shedding 2-3 pounds of fat a week.
Don't listen to the naysayers, just pick up some Modalert 200, use it daily for a couple of weeks, and draw your own conclusions.
PS: If you're coming off that horrible adderall garbage, you need to be at least a month clean, because you need to be closer to baseline dopamine levels or the lingering effects of amphetamine induced dopamine depletion will interfere with the way Moda works.