[SKB_Hamsters]

You shouldn't feel guiltily about housing your past hamsters in small cages as most of us on the forum have done the same. I can completely relate to how you feel as I also used feel bad about my previous hamster being houses in cages which were much smaller than my current DIY cage, but I still gave them the same amount of love as I currently give my Pumpkin - which is the most important thing to remember!
It best to try to forgive yourself and continue to spoil your current hamster rather than holding onto the guilt. As you will start to feel better for it - as I know it help me to forgive myself for doing the same.