It depends actually, but there are hard parts. First couple of segments are easier than others.
Goods
This is a great trail - it is long, it has a lot of diversity in it, has some unique features (like that wooden climb, have never seen that before).
It is in a great location - Nuuksio is a national park for a reason.
It has good on trail navigation.
There are two parking places nearby, so it's easy to reach. Technically, it's not too hard to get there from Espoo on your own.
Bads
Unlike the original Oittaa MTB, or EKP trails - this one is actually a set of segments, somewhat like Helsingin keskuspuisto one. And the navigation between them is not that good - I've had an official gpx and still nearly missed a segment.
It is not one way. There are fast enough parts where it might be dangerous. So watch out.