Will's 'recipe':
All mine get fed once every 4 days, instead of one big meal every 7-10 days. Pretty much keeps something in their bellies at all times, without endng up with fat snakes -- at least not yet...
All prey sizes - One item every 4 days until they take 2 per feeding for a few feedings and then I bump them up to the next size and start all over. When you bump them up from, say fuuzies to hoppers, pick out the smallest hopper you have, don't just toss in a mutant-giant-mouse either though, they should be able to handle it.
Once they reach adults they get fed one large mouse every 4 days. I don't bump them to 2 adult mice every 4 days, unless it is a female getting ready to breed, in which case she'll get a bit more. The growth rates seem to be great, without ending up with obese snakes, I have one yearling Cal that went from 70g to 220g and countng -- and I got her in May. My 3 or 4 month old Honduran males are already downing single hoppers with no complaints, I think they weigh in the mid-60g range right now. Sorry , no lengths.
If you can invest in a decent postal scale,
THIS SITE is pretty neat. It tells you how much you "should" be feeding your snake. Keep in mind, different snakes have different metabolic rates(Kings will use more energy compared to body mass than a less active species would), and is using mice as athe food source, so you don't have to follow the chart to the "T", but it is a helpful guideline to see whether you are feeding it enough.