I didn't make it to the race a couple of weeks ago but I did go to the fundraiser on Saturday. Overall, it is a fun trail and I wouldn't hesitate to go back if/when they open the trails to the public. Here is a quick rundown. It is set up nicely where the easiest loop connects to the middle loop, which connects to the hardest loop.
Performance Trail (4 miles) - this is the loop the NICA teams race on. Fairly flowy, not a whole lot of elevation but not pancacke flat, either. Fun to loop around or tack on a few extra miles after your legs are already tired. Maybe 65% similar to Yargo and 35% similar to the Mill trails at Rope Mill.
Turbine (1.5 miles) - Adds some punchy climbs and a little more technical challenge, though still doable by a beginner who is up for a challenge. The most technical parts are some off-camber sections.
Factory (1.5 miles) - More technical and punchier. I was on a hardtail with Fastrack tires and was fine, but it was early in the day and pretty slippery from some overnight rain, so I was sliding around a good bit and wishing for more grip. I'd put the difficulty level somewhere around South Loop, but the climbs were shorter and packed together more, if that makes sense.
The whole ~7 mile loop was a little more difficult than I expected, but still fine for an intermediate rider on a hardtail (which is what I consider myself). The back loop is the type where moisture cranks up the challenge. One interesting thing is that you can hear the race cars going around the track, which is both neat and annoying.
