Love it, love when people confirm my bias.
1XRP 1BTC
WHEN?
Your question proves a lot about you

and believe me, not good things. If you ask such question you should not be here at all

e.g.
Are you asking when XRP will be price of BTC? What price should be BTC that it would be equal to XRP? Does it mean that BTC looses value? Does it mean that XRP gets value? Does it means BTC looses XRP gains and they meet somewhere? and list of questions continues...
Love it, love when people confirm my bias.
1XRP 1BTC
WHEN?
1 XRP = 1 dollar When?
I would bet on first half of 2018, but all my predictions so far were too cautious.
e,g, if by EOY BTC will settle all never ending disputes, than it can be 4000USD easilly, in this case XRP has to be 0.00025 to meet 1 USD. Market capacity for this case has to be 70-80B for BTC and 40-50B for XRP, though I do not think that BTC market cap always should be dominant in trully decentralised world.
You can read more, on some analysis, again on people that speak more than all trolls:
https://www.xrpchat.com/topic/5233-relative-markets-and-analysis/