I dont't use a steriliser.
I use the very traditional method, less complicated (I think)
I sterilise the bottles every morning.
Put them in boiling water, then turn off the gas and leave the bottles and teats and bottle covers inside for about 10mins
For the rest of the day, I'll just wash the bottles and teats with the bottles brushes and the teats brushes, thereafter put them inside a container of boiled water.
This is what I do when my babies has stop the breastfeeding period, which is when they are 4 month old (elder one) and 7 month old (younger one)