If it helps with your decision (and if I've counted correctly), ROTR did not open for rope drop for 7 of the 31 days in October. Based on that, there's a 20-25% chance that it won't be open for rope drop the day of your visit either.
That is not a great number to make plans on. The concern is that you won't be told the ride is down until rope drop. And at that point, going somewhere else would put you at the back of the line, pretty much wiping out any advantage you have from getting to the park at rope drop.
ROTR is one of the least-reliable rides in WDW, averaging just under 2 hours of downtime per day over the last couple of years. If it's in your budget, the best way to avoid the risk of waiting in line without riding is to purchase ILL.