fuel injection

ok so is it sequental where each injector fires at a different time? or is that where they go all at the same time? and what are the advantages of both? i have always liked the seperate kind so each cylinder gets a "mist" of gas rather then liguid but how much would this help?

and where can i look at prices for megasquirt? and what are good competitors to look at what the others are? like i said in another thread this is for my girls future car so proabably wont get something to soon but would like to look at it