So I bought a pair of the nike zoom rival waffle 6 and am now running on them on the roads. It took some time to get the sizing right. These shoes are very narrow. Despite being unisex, I'd say they are B width at best - meaning if you are a woman, you might feel they fit normally ha.
I don't know if I can do all my training in these bc of how narrow they are, but we'll see. I found sizing up half a size works best - took some trial and error to figure out, which considering I have to buy shoes online these days is super annoying - just study the human foot to size your shoes nike.
Anyways, the shoe has more give and is softer than the streak lt, but tighter. If I hadn't been training in the streak lts these would be too tight. The heel is especially tight. You'll want to do heel exercises to strengthen your ankles if you are going to run in these. Despite being made for xc, the traction on this shoe is not great. I don't think I'd race in them in the rain and I definitely wouldn't run with them on a muddy course.
I imagine the guy who ran 15 miles in them probably does a lot of running in spikes already. Wearing spikes for a significant amount of training is the only way I could see someone reporting this shoe as great.
The shoe is more forgiving than the streak lt 3 and 4, except in the ankle and less forgiving than the xc 1, 2, and 3, and lt 1 and 2. I rate it subpar compared to how a racing flat should feel - like the streak xc 1 - lt 2, but its probably the best thing on the market and you can run with it on the roads. I'm not sure about long runs in these though bc they are so tight.