This is very true but a few little issues come with this. Normally when you buy adults they are usually old breeders and much more expensive. Even if you want to save the extra buck and go with the mixed lot yes you will have to wait for them to mature and have more males then females but at least you will have 18-20 months of breeding from the females. I think if you add the pennies it is a money saver and in the long run a time saver. It may feel like you are getting somewhere if you get adults from the get go but really the disadvantages out weigh the advantages. For the same amount of money as a lot of adults you could get 5 times as many nymphs. Just a few months of waitng and your colony will be much larger then if you would have bought adults. I have done both methods and that is what lead me to this conclusion..