JCP growth and caging questions...

I have a young male JCP, I think around 7 months old now... he's still fairly small at maybe 60-70g, and living in the 6qt tub I originally gave him. He spends 99% of the time perched on his branch, and doesn't seem like he's outgrown the tub yet. I did get him a 15qt the other day, and it seemed like a good size - but was unfortunately the wrong height for my rack. :cool:

So here are my questions, as this my first (and only) Carpet Python - does it sound like he's growing okay, and is he ready for a tub upgrade? What size Sterilite tubs would you recommend for a growing JCP, and at what stages do you typically upgrade? Also, how long does it take for a JCP male to reach full size? He's currently feeding on small f/t hopper mice, and it leaves a very noticeable lump... so can I assume that's a good sized prey? TIA for any advice! Here are some recent photos of Kipling, so you can judge his size & tub space:

(please excuse the log of poo - should have cleaned before taking the photo, LOL.)
http://i131.photobucket.com/albums/p...3/P1010173.jpg

http://i131.photobucket.com/albums/p...3/P1010179.jpg

Just thought this shot was cute... ;)
http://i131.photobucket.com/albums/p...3/P1010177.jpg

Oops, I meant to post this in "Morelia!" Moderators, feel free to move it if that's a better place...