Haven't heard of Springboost before, but they appear legit.
It's says they are women's, but when you add to cart, it appears as mens, although I would say they may be unisex anyway.
Seems they are targetted towards volleyball, but I am sure you can just wear them like normal shoes…will find out soon enough, after ordering a pair last night ; )
Features:
- Includes three interchangeable insoles corresponding to the three separate degrees of "Dorsiflexion"
- Schoeller Keprotec fabric made of Kevlar fibers for tear resistance and durability.
- Fabric and leather upper, padded collar and tongue, full lace up closure, and non-marking textured sole
Couldn't find much info about them (looks like they are a discontinued model?):
http://www.springboost.com/en/dorsiflexion/dorsiflexion_biom…
http://www.amazon.com/Springboost-Mens-B-Spike-Volleyball-Sh…
Looks like their association with FIMS is genuine:
http://www.fims.org/en/partners/springboost/
Zavvi sizing guide:
http://www.zavvi.com/size-charts.info?q=mens-footwear-chart4
+1 from me for a thoroughly researched post, unfortunately only available in UK sizes 5.5-8, which is not for me.
Those confused with AU vs US vs UK vs Gender sizing will find this table much more helpful than Zaavi's own sizing guide: http://www.aussiethings.com.au/articles.php?article=13