I've been feeding my yearling fuzzy rats once a week & she's growing like a weed! She's shedding once a month for the last 4 months! I prefer rats, personally, feel like they're getting more bang for the buck than w/ mice.
About your size ?, I have an adult (6 years old when we got him this past summer) who's about 52" long & currently weighs a kilogram (1,000 grams)! He was eating adult rats when he went off feed a few weeks ago for the winter. 
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2.1 Corn snakes Snake Plissken, Jack Skellington & Abby
1.1 Hog Island Boas Harley & Isaboa
1.3 leos, Yoda, Geo, Tang, Ginger
1.0 Blue Tongue Skink Indigo (Indy)
0.1.1 frogs Buffy the Cricket Slayer, Butrose Butrose Froggy
1.1.5 firebelly newts Wayne Newton, Isaac Newton, Fig Newton, Juice Newton, Olivia Newton John, Helmut Newton & Thandie Newton
1.1 cats Gus & Mena
