Thanks a lot everyone, yes I'm using Cfls, why shouldn't I wait till they get too big?
Because you wont get enough light to penetrate to the bottom of the plants if they get to tall by using CFLs. That is unless if you either have a lot of CFLs at the bottom as well as on top or if you do LST (low stress training).
If I were you I wouldnt let them get so tall, but thats just me

For cloning look at this, it was posted on our FAQs

http://boards.cannabis.com/showthread.php?t=23400