Cheers for the replies - text sent Tom, thanks.
Ian and Winpro - I had thought about DI only, but my worry is that if I get the bottles that I have filled and set up and then it turns out that I can't get a long-term fix with storage, then I'm only going to re-invest getting RO installed... I guess my worry is the sheer cost of Resin.
Oh and Winpro - is there an online map showing local ratings as I'm not sure. I'm also not familiar with how that would be more efficient with the twins, no.
Joe