Early reports on new skis are usually glowing reports and cheerleading from people that are financially tied to the brand. It takes a year or two for a new ski to be tested and reviewed by real world paying customers. This is still early days for the nelo 600.
I saw the ski in action in the columbia river gorge this summer. It was surfing very well in steep waves, but with world champions piloting it, that was no surprise.
A friend of mine owns one. It seems like a good ski so far but the steering on the wave is mushy and then over reacts. Part of that may be the rather unusual rudder it comes with. Of note, that is NOT the rudder that was being used by Oscar in the gorge. I believe he was using a Don Kiesling custom rudder out there. Also, some of the nelos that have been made thus far have had rather elastic steering lines that have to be replaced by the owner. Both of the 560s in my area had that problem. I am not sure if that is the case with my friend’s 600, but it is something to be aware of. Goofy rudder and lines are not really a deal breaker as they can be changed, but something to be aware of.
Regarding the epic double I would compare it to the v8 double rather than the v10 double. Another friend owns the v8 double. It is a great ski downwind, though a very wet ride.
Current Skis: Nelo Vanquish AIR, Epic V10g4, NK 670 double, NK exrcize, Carbonology Feather, Think Jet, Knysna Sonic X
Former Skis: Epic v10g3, Kai Waa Vega, Epic V12 g2, Epic V12 g1, Epic v10 double, Nelo 550 g2, Fenn Elite S, Custom Kayaks Synergy