@Groucho - When you were making ARF withdrawals, did you get any Class S PRSI contributions added to your total?
Yes Dave, Zurich paid me net of PAYE, USC and PRSI.
Although I'm aware of the €500 stated minimum, I'm also aware that in practice if you make a withdrawal each year from an ARF you will be credited with Class S PRSI even if your PRSI deduction is less than €500. I think this is also @bstop 's personal experience, from what I've read here.
I suspect that you're correct about that. I was told (off the record) by someone in Social Welfare not to worry about paying the €500 as my Class S credits would be added anyway - but I didn't want to take the risk!