Nike Zoom Victory XC 3? Thinking about purchasing these spikes for the season but they sell for around $120. A bit pricy. Should I just buy the Rivals or do you think the XC 3's are worth the $$$? Also, would you laugh at a runner with a PR just under 20 min. in the 5k wearing these. I feel like you need some merit to be worthy of wearing high-end spikes. Thoughts and opinions please.