Comparing side by side with CDR 4700uf 50v, I found Keltron to be physically bigger as well as heavier.
Don't know if that matters.
Also it may be possible that CDR uses more advanced technology to reduce physical footprint of their caps.
I use Keltron electrolytic caps regularly. Mostly in the power supply. It's easily available in Kolkata, cheap and causes no discernible degradation of sound.
Regards