The other day I was gifted both the Feather Popular and the Feather Adjustable razor for my birthday. I did hear some springy sounds while twisting the knob to open the butterfly doors, so I took a little bit of oil and poured it down the centre to lubricate the moving parts. What I wanted to know was, with regular lubrication (maybe once a month?) and decent usage (three shaves a week), how many years can I get out of my razor? Does water going down the centre cause corrosion easily? If so, how do I ensure that the metal components don't corrode? Thank you guys for your answers!