Which is more accurate actual price or estimated price? I don't think either are for the cpu algo I am mining(m7m on hashrefinery other m7m pools are lower) at $1.89. It's like at that plausible price tso not sure.
Looking at the 24 hour chart for m7m on HashRefinery, there were some insane price spikes with that algorithm earlier today - almost 2000 mbtc/Mh/day, so the price you saw was coming from the pool based on its estimates. It looks like there are more orphan Magi coins than real coins today on that pool, which is probably why the prices are skewed. The Price Spike Limit feature will also work for the CPU if you want to avoid having the CPU mine coins experiencing these kinds of pool issues.
To answer your question, the actual prices reflect the historic prices from the previous day while the estimates are based on more recent data. If the coin's price has been steady in the past day, the actual price should be more accurate. However, if the price of the coin has risen or fallen significantly in the past 24 hours, the estimated price may be more accurate.