People tend to whinge about the Marin because of the initial climb out of the car park. It’s approx a 15-20 climb on fire road but then you are rewarded to a lovely bit of singletrack.
It’s the nature of the terrain there that gives it some of the fire road climbs but at the end of every climb there is a singletrack section.
If you don’t like fire road climbs you will have forgotten all about them after completing the last decent to the carpark.
If you are up here, dont pass it by otherwise you will never know. I’ve done it hundreds of times and never tire of it.
There has been some trail maint and they have tamed some of the more technical or washed away sections but it’s still good.