Is my bp underweight?

I have a normal thats between 2 and 3 ft (the one im worried about) and a mojave thats under 2ft. The mojave is a male 2011 and when i got him about a month ago he was said to be 200g. i have no idea how much my normal weighs cuz i dont own a scale annnd i got it from a pet store so i dont know the gender either, im guessing a female. i also dont know how old it is but im guessing 2 years cuz iv already had it a year (darn petco >_< dont know anything bout my snake) Anyways im worried cuz my normal really doesnt look all to thick next to my mojave.. and i know balls are supposed to look pretty.. robust? lol like not the same thickness all the way through. Let me know you guys' opinions and how to chubben her up the correct way (feeding more often or bigger food?) I just found her after losing her for a while and iv been feeding her full grown f/t mice. for comparison, i feed the mojave f/t hoppers.

Alone:
http://i1057.photobucket.com/albums/...p/DSCN0268.jpg

Side by side comparison:
http://i1057.photobucket.com/albums/.../boo1004-1.jpg

Head size (normal is lacking cheek chub if you can tell):
http://i1057.photobucket.com/albums/...up/boo1006.jpg

She could put some weight on, but she doesn't look unhealthy at this point. They all grow at their own rate.

doesnt look too thin

I agree, neither snakes looks really thin. They all grow at different rates, and some get longer before they get thicker.

My hubby has a pinstripe girl, she is so short that she looks ridiculously fat, even though she isn't. She weighs the same as my cinnamon girl, but my cinnamon is a solid 8" longer and looks pitifully thin beside the pinstripe.

As long as both eat well and consistently for you, I wouldn't worry too much. When they start actively hunting a few days before the regular feeding day every week, that's usually the hint I rely on to bump up prey size.

Gale