I have always been a long term holder so anytime is a good time if you are in long enough.
With the resent news about Korea it's taking a bashing and I think it's at a good price to get in at the minute. Just don't be looking at getting out in the next 6 months to 2 years. It's going to be rough times and you are not going to get your quick returns like you can with some of the alts