Bambo Nature Diapers

I really like these diapers but the sizing scale is crazy the size 3 diaper weight is 11lbs to 20lbs. My son has now grown out of them but still cant wear a size 4 in regular diapers. So i bought some size three dg baby premium diapers the size of these are from 16lbs to 28lbs. And way more affordable for $5.50. My son is 20lbs i had to ask his dad to get him some diapers. But i also dont want him to spend alot of money on huggies, pampers, i was buying loves but even he had to move up but had to keep moving up i also dont want him to think i just put his son in cheap diapers. But right now i take any size diapers cause the bambo nature ones have gotten to tight for his legs.